Tuesday, July 27, 2010

Digital Mode Programs That Work #2: Multipsk

Multipsk is a multimode receive/transmit program that works with the PC sound card in Windows or Linux. It's rapidly becoming the big gun in freely available ham/SWL software for these platforms.

The program is by Patrick Lindecker, F6CTE. It can be downloaded from Patrick's F6CTE web site, which is in English. A Yahoo group (also in English) for users is reachable at Multipsk (at) yahoogroups.com. I haven't looked at this group, but I keep meaning to.

Just about everyone I can think of who uses Windows or Linux for serious utility work has at least tried this program. Now that SkySweeper is no longer supported, Multipsk is the most viable PC multimode package for under $3000 US. WAY under, in fact, since a perfectly acceptable version is available free. As in $0000 US. This is not crippleware or nagware. When you pony up the $45 (last I looked), you get more features, and lose the time limits on some others.

New versions come out on a regular basis, and most add at least one new mode. The latest is 4.18. The major change from 4.17 is the addition of US weather radio SAME (Specific Area Message Encoding) decode. I've played with SAME on my scanner a bit. Its purpose is to alert local areas for bad weather.

The list of other modes is boggling:

110A (MIL-STD-188-110A/B), 1382 (1200 baud MSK), STANAG 4285, VHF ACARS, ALE, AMTOR/SITOR, ASCII, BPSK/QPSK 32/63/125/250, CHIP 64/128, Contestia, Coquelet, CW (OOK/Coherent/FSK), DGPS, Domino, DSC, DTMF, FAX, Hellschreiber (Feld/PSK/FM), JT65, MFSK8/16, MT63, Olivia, Packet/APRS, Pactor-I (used mostly for calling), PAX, PSK10/63F/220F, PSKAM, QRSS, RTTY, SELCAL, SSTV, and THROB.

Whew.

Hams will be able to take advantage of many features for logging, radio control (with 3rd-party software), and display of things like maps. For utility, the later versions have steadily added "professional" modes, such as SITOR-A, non-amateur RTTY speeds and shifts, and a SYNOP decoder (time limited w/o registration). Now, if I could only get good skip on Hamburg Meteo when the SYNOP codes are on.

The package includes another program called Clock, which decodes the data hidden in most time signals and GPS. After registration, it can set your computer clock. I've used this on several low-frequency European time signals via the WebSDR in Holland. This is close to a worst case for decode, given the Internet link's general instability. With considerable patience, though, I've managed decodes on nearly all stations at one time or another.

Anything this complicated is going to have a learning curve. Also, many people have been intimidated at first by the user interface. Now, I have come to like this. It's way faster than going through menus or trying to remember presets when you're in a hurry to grab onto some signal. The downside, though, is that there really are a lot of little buttons.

The colors have also turned some people off, though I don't mind them at all. They help group the aforementioned little buttons in a fairly logical manner.

How do the decodes stack up against other programs? Most of the time, just fine. I like SkySweeper better for FAX, but a lot of people hate it. DGPS might be better than SkySweeper, though DSCdecoder beats them both. SIGMIRA is somewhat better than either for STANAG 4285, though that mode really pushes the edge for any sound card decoder.

Where Multipsk has the general edge, for me anyway, is its use as a tool for attacking completely weird signals. This is especially true for the PSK variants.

I realize that the high-end government packages are often pretty good at this. But they aren't free/ $45. Case closed.

Saturday, July 24, 2010

Air Recon Taskings for Bonnie 24-26 July (Note NOAA Canx)

000
NOUS42 KNHC 241330
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
0930 AM EDT SAT 24 JULY 2010
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 25/1100Z TO 26/1100Z JULY 2010
TCPOD NUMBER.....10-054

I. ATLANTIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. SUCCEEDING DAY OUTLOOK.....NEGATIVE.
3. REMARKS: NOAA P-3 OPERATIONAL FLIGHTS FOR 24/0800Z
AND 24/2000Z WERE CANCELED AT 24/0200Z. THE P-3
IS NOW SCHEDULED FOR A RESEARCH MISSION DEPARTING
MACDILL THIS AFTERNOON AT 24/1600Z.

II. PACIFIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. OUTLOOK FOR SUCCEEDING DAY.....NEGATIVE.
JWP

Tropical Depression Bonnie Advisory Number 9

000
WTNT33 KNHC 241434
TCPAT3
BULLETIN
TROPICAL DEPRESSION BONNIE ADVISORY NUMBER 9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL032010
1000 AM CDT SAT JUL 24 2010

...BONNIE HANGING IN THERE WITH 30 MPH WINDS...TROPICAL STORM WARNINGS DISCONTINUED...


SUMMARY OF 1000 AM CDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...28.0N 86.7W
ABOUT 165 MI...265 KM ESE OF THE MOUTH OF THE MISSISSIPPI RIVER
ABOUT 155 MI...250 KM SW OF APALACHICOLA FLORIDA
MAXIMUM SUSTAINED WINDS...30 MPH...45 KM/HR
PRESENT MOVEMENT...WNW OR 300 DEGREES AT 17 MPH...28 KM/HR
MINIMUM CENTRAL PRESSURE...1014 MB...29.94 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...

ALL TROPICAL STORM WARNINGS ARE DISCONTINUED

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

NONE.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA IN THE UNITED STATES...PLEASE MONITOR PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST OFFICE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1000 AM CDT...1500 UTC...THE CENTER OF TROPICAL DEPRESSION BONNIE WAS LOCATED NEAR LATITUDE 28.0 NORTH...LONGITUDE 86.7 WEST. THE DEPRESSION IS MOVING TOWARD THE WEST-NORTHWEST NEAR 17 MPH...28 KM/HR. THIS GENERAL MOTION IS EXPECTED TO CONTINUE AS THE CENTER MOVES INLAND OVER THE NORTHERN GULF COAST BETWEEN SOUTHEAST LOUISIANA AND ALABAMA TONIGHT.

MAXIMUM SUSTAINED WINDS ARE BARELY 30 MPH...45 KM/HR...WITH HIGHER GUSTS. THESE WINDS ARE CONFINED TO A FEW RAINBANDS MAINLY TO THE NORTH OF THE CENTER. NO CHANGE IN STRENGTH IS FORECAST BEFORE THE CENTER REACHES THE COAST. A GRADUAL WEAKENING IS EXPECTED AS THE SYSTEM MOVES INLAND.

ESTIMATED MINIMUM CENTRAL PRESSURE FROM A RECONNAISSANCE AIRCRAFT WAS 1014 MB...29.94 INCHES.


HAZARDS AFFECTING LAND
----------------------
WIND...ISOLATED GUSTS TO TROPICAL STORM FORCE WINDS IN SQUALLS ARE LIKELY TO SPREAD OVER PORTIONS OF THE NORTHERN GULF COAST...FROM SOUTHEAST LOUISIANA EASTWARD TO THE FAR WESTERN FLORIDA PANHANDLE LATER TODAY.

RAINFALL...BONNIE IS EXPECTED TO PRODUCE TOTAL RAINFALL ACCUMULATIONS OF 1 TO 2 INCHES OVER PORTIONS OF SOUTHERN LOUISIANA...SOUTHERN ALABAMA...SOUTHERN MISSISSIPPI...AND THE FAR WESTERN FLORIDA PANHANDLE...WITH POSSIBLE ISOLATED MAXIMUM AMOUNTS OF 3 INCHES.


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...400 PM CDT.

$$
FORECASTER AVILA/ROBERTS

Friday, July 23, 2010

Air Recon Taskings for Bonnie 24-25 July

000
NOUS42 KNHC 231530
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1130 AM EDT FRI 23 JULY 2010
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 24/1100Z TO 25/1100Z JULY 2010
TCPOD NUMBER.....10-053

I. ATLANTIC REQUIREMENTS
1. TROPICAL STORM BONNIE
FLIGHT ONE -- TEAL 70
A. 24/1800, 2100, 25/0000Z
B. AFXXX 1003A BONNIE
C. 24/1630Z
D. 28.2N 88.5W
E. 24/1700Z TO 25/0000Z
F. SFC TO 15,000 FT

FLIGHT TWO -- NOAA 42
A. 25/0000Z
B. NOAA2 1103A BONNIE
C. 24/2000Z
D. NA
E. 24/2100Z TO 25/0300Z
F. 12,000 FT

FLIGHT THREE -- TEAL 71
A. 25/0300, 0600, 0900Z
B. AFXXX 1203A BONNIE
C. 25/0030Z
D. 29.3.0N 89.0.0W
E. 25/0200Z TO 25/0900Z
F. SFC TO 15,000 FT

2. SUCCEEDING DAY OUTLOOK: NEGATIVE.
3. REMARKS:
A). NOAA'S P-3 WILL FLY OPERATIONAL MISSIONS
THIS AFTERNOON AT 23/2000Z AND IN THE MORNING AT
24/0800Z. OPERATING ALTITUDE IN THE STORM
ENVIRONMENT WILL BE 12,000 FT.
B). G-IV MISSION SCHEDULED FOR 24/0000Z CANCELED
BY NHC AT 23/1110Z.

II. PACIFIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. OUTLOOK FOR SUCCEEDING DAY.....NEGATIVE.
JWP

Tropical Storm Bonnie Advisory Number 3

Bonnie is now a tropical storm. Models show a gradual curve which would take the center very close to the oil spill area. The effect will depend on how organized a currently rather disorganized tropical storm becomes.

The oil spill efforts are largely halted, and hurrevac procedures have begun. Check the usual frequencies, plus US Coast Guard simplex.

--------------------

000
WTNT33 KNHC 230242
TCPAT3
BULLETIN
TROPICAL STORM BONNIE ADVISORY NUMBER 3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL032010
1100 PM EDT THU JUL 22 2010

...CENTER OF BONNIE APPROACHING THE NORTHWESTERN BAHAMAS...NEW TROPICAL STORM WARNINGS FOR SOUTHERN FLORIDA...


SUMMARY OF 1100 PM EDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...23.4N 76.5W
ABOUT 125 MI...200 KM SSE OF NASSAU
ABOUT 285 MI...460 KM SE OF MIAMI FLORIDA
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/HR
PRESENT MOVEMENT...NW OR 305 DEGREES AT 14 MPH...22 KM/HR
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...

A TROPICAL STORM WARNING HAS BEEN ISSUED FOR THE EAST COAST OF FLORIDA NORTH OF GOLDEN BEACH TO DEERFIELD BEACH.

A TROPICAL STORM WARNING HAS BEEN ISSUED FOR THE WEST COAST OF FLORIDA NORTH OF BONITA BEACH TO ENGLEWOOD.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* CENTRAL AND NORTHWESTERN BAHAMAS
* FOR THE FLORIDA EAST COAST FROM DEERFIELD BEACH SOUTHWARD INCLUDING THE ENTIRE FLORIDA KEYS AND FLORIDA BAY...AND ALONG THE WEST COAST OF FLORIDA NORTHWARD TO ENGLEWOOD

A TROPICAL STORM WATCH IN IN EFFECT FOR...
* THE EAST COAST OF FLORIDA NORTH OF DEERFIELD BEACH TO JUPITER INLET INCLUDING LAKE OKEECHOBEE

A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED SOMEWHERE WITHIN THE WARNING AREA WITHIN 36 HOURS.

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA.

INTEREST ALONG THE NORTHERN GULF COAST SHOULD MONITOR THE PROGRESS OF BONNIE. WATCHES MAY BE REQUIRED FOR PORTIONS OF THE NORTHERN GULF COAST ON FRIDAY.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA IN THE UNITED STATES...INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST OFFICE. FOR STORM INFORMATION SPECIFIC TO YOUR AREA OUTSIDE UNITED STATES...PLEASE MONITOR PRODUCTS ISSUED BY YOUR NATIONAL METEOROLOGICAL SERVICE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1100 PM EDT...0300 UTC...THE CENTER OF TROPICAL STORM BONNIE WAS LOCATED NEAR LATITUDE 23.4 NORTH...LONGITUDE 76.5 WEST. BONNIE IS MOVING TOWARD THE NORTHWEST NEAR 14 MPH...22 KM/HR. A TURN TOWARD THE WEST-NORTHWEST AND A FASTER FORWARD SPEED ARE FORECAST ON FRIDAY. ON THE FORECAST TRACK...THE CENTER OF BONNIE IS EXPECTED TO PASS NEAR OR OVER THE FLORIDA KEYS AND THE SOUTHERN FLORIDA PENINSULA ON FRIDAY...AND MOVE INTO THE EASTERN GULF OF MEXICO FRIDAY NIGHT AND SATURDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER GUSTS. SLOW STRENGTHENING IS POSSIBLE DURING THE NEXT 48 HOURS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 45 MILES...75 KM MAINLY TO THE NORTHEAST OF THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB...29.74 INCHES.


HAZARDS AFFECTING LAND
----------------------
WIND...TROPICAL STORM CONDITIONS WILL SPREAD OVER THE CENTRAL AND NORTHWESTERN BAHAMAS TONIGHT AND FRIDAY. WEATHER CONDITIONS WILL BEGIN TO DETERIORATE ON THE FLORIDA COAST AND FLORIDA KEYS WITHIN THE WARNING AREA EARLY FRIDAY MORNING.

RAINFALL...BONNIE IS EXPECTED TO PRODUCE TOTAL RAIN ACCUMULATIONS OF 2 TO 4 INCHES OVER SOUTH FLORIDA...WITH POSSIBLE ISOLATED MAXIMUM AMOUNTS OF 6 INCHES. RAINFALL AMOUNTS OF 3 TO 5 INCHES ARE EXPECTED OVER THE CENTRAL AND NORTHWEST BAHAMAS...WITH POSSIBLE ISOLATED AMOUNTS OF 5 TO 7 INCHES.

STORM SURGE...STORM SURGE WILL RAISE WATER LEVELS BY AS MUCH AS 1 TO 2 FEET ABOVE GROUND LEVEL OVER PORTIONS OF THE BAHAMAS...THE FLORIDA KEYS...AND THE SOUTHERN FLORIDA PENINSULA.


NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...200 AM EDT.
NEXT COMPLETE ADVISORY...500 AM EDT.

$$
FORECASTER BEVEN

Thursday, July 22, 2010

Air Recon Taskings for TD-3 22-23 July

000
NOUS42 KNHC 211500
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1100 AM EDT WED 21 JULY 2010
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 22/1100Z TO 23/1100Z JULY 2010
TCPOD NUMBER.....10-051

I. ATLANTIC REQUIREMENTS
1. SUSPECT AREA (NORTH OF CUBA)
FLIGHT ONE -- TEAL 70
A. 22/1800Z
B. AFXXX 02BBA INVEST
C. 22/1430Z
D. 23.0N 76.0W
E. 22/1700Z TO 21/2300Z
F. SFC TO 10,000 FT

FLIGHT TWO -- NOAA 49
A. 23/0000Z
B. NOAA9 03BBA SURV
C. 22/1730Z
D. NA
E. NA
F. 41,000 TO 45,000 FT

FLIGHT THREE -- TEAL 71
A. 23/0600Z, 1200Z
B. AFXXX 0403A CYCLONE
C. 23/0300Z
D. 24.5.0N 78.5.0W
E. 23/0500Z TO 23/1200Z
F. SFC TO 15,000 FT

2. SUCCEEDING DAY OUTLOOK: BEGIN 3-HRLY FIXES AT 23/1500Z
IF SYSTEM DEVELOPS. A POSSIBLE G-IV MISSION FOR 24/0000Z

3. NOTE: THE AF MISSIONS TASKED FOR 21/1800Z, 22/06-1200Z
WERE CANX BY NHC AT 21/1130Z. THE GIV MISSION TASKED FOR
21/1730Z WILL FLY.

II. PACIFIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. OUTLOOK FOR SUCCEEDING DAY.....NEGATIVE.
WVW


000
NOUS42 KNHC 221430
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1030 AM EDT THU 22 JULY 2010
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 23/1100Z TO 24/1100Z JULY 2010
TCPOD NUMBER.....10-052

I. ATLANTIC REQUIREMENTS
1. TROPICAL DEPRESSION THREE
FLIGHT ONE -- TEAL 75
A. 23/1500, 1800, 2100Z
B. AFXXX 0503A CYCLONE
C. 23/1200Z
D. 24.1N 80.8W
E. 23/1430Z TO 23/2100Z
F. SFC TO 15,000 FT

FLIGHT TWO -- NOAA 49
A. 24/0000Z
B. NOAA9 0603A CYCLONE
C. 23/1730Z
D. NA
E. NA
F. 41,000 TO 45,000 FT

FLIGHT THREE -- TEAL 76
A. 24/0000, 0300, 0600Z
B. AFXXX 0703A CYCLONE
C. 23/2130Z
D. 25.0.0N 83.2.0W
E. 23/2300Z TO 24/0600Z
F. SFC TO 15,000 FT

FLIGHT FOUR -- TEAL 77
A. 24/0900, 1200, 1500Z
B. AFXXX 0803A CYCLONE
C. 24/0700Z
D. 25.7N 85.6W
E. 24/0800Z TO 24/1500Z
F. SFC TO 15,000 FT

2. SUCCEEDING DAY OUTLOOK: CONTINUE 3-HRLY FIXES.

II. PACIFIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. OUTLOOK FOR SUCCEEDING DAY.....NEGATIVE.
JWP
53

Tropical Depression Three Public Advisory #1

[This depression has the potential to develop into Bonnie, and early predictions show its northwest quadrant passing directly through the oil spill area. -Hugh]

------------------

000
WTNT33 KNHC 221459
TCPAT3
BULLETIN
TROPICAL DEPRESSION THREE ADVISORY NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL032010
1100 AM EDT THU JUL 22 2010

...TROPICAL DEPRESSION FORMS IN THE BAHAMAS...AIR FORCE RECONNAISSANCE PLANE EN ROUTE...


SUMMARY OF 1100 AM EDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...21.9N 75.0W
ABOUT 265 MI...425 KM SE OF NASSAU
ABOUT 405 MI...655 KM ESE OF KEY LARGO FLORIDA
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/HR
PRESENT MOVEMENT...WNW OR 295 DEGREES AT 15 MPH...24 KM/HR
MINIMUM CENTRAL PRESSURE...1008 MB...29.77 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...

THE GOVERNMENT OF THE BAHAMAS HAS ISSUED A TROPICAL STORM WARNING FOR THE CENTRAL AND NORTHWESTERN BAHAMAS.

A TROPICAL STORM WARNING HAS BEEN ISSUED FOR THE FLORIDA EAST COAST FROM GOLDEN BEACH SOUTHWARD INCLUDING THE ENTIRE FLORIDA KEYS AND FLORIDA BAY...AND ALONG THE WEST COAST OF FLORIDA NORTHWARD TO BONITA BEACH.

A TROPICAL STORM WATCH HAS BEEN ISSUED FOR THE EAST COAST OF FLORIDA FROM NORTH OF GOLDEN BEACH TO JUPITER INLET INCLUDING LAKE OKEECHOBEE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* CENTRAL AND NORTHWESTERN BAHAMAS
* FOR THE FLORIDA EAST COAST FROM GOLDEN BEACH SOUTHWARD INCLUDING THE ENTIRE FLORIDA KEYS AND FLORIDA BAY...AND ALONG THE WEST COAST OF FLORIDA NORTHWARD TO BONITA BEACH

A TROPICAL STORM WATCH IN IN EFFECT FOR...
* THE EAST COAST OF FLORIDA NORTH OF GOLDEN BEACH TO JUPITER INLET INCLUDING LAKE OKEECHOBEE

A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED SOMEWHERE WITHIN THE WARNING AREA WITHIN 36 HOURS.

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 48 HOURS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA IN THE UNITED STATES...INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST OFFICE. FOR STORM INFORMATION SPECIFIC TO YOUR AREA OUTSIDE UNITED STATES...PLEASE MONITOR PRODUCTS ISSUED BY YOUR NATIONAL METEOROLOGICAL SERVICE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1100 AM EDT...1500 UTC...THE CENTER OF NEWLY FORMED TROPICAL DEPRESSION THREE WAS LOCATED NEAR LATITUDE 21.9 NORTH... LONGITUDE 75.0 WEST. THE DEPRESSION IS MOVING TOWARD THE WEST-NORTHWEST NEAR 15 MPH...24 KM/HR. THIS GENERAL MOTION WITH AN INCREASE IN FORWARD SPEED IS EXPECTED DURING THE NEXT 48 HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/HR...WITH HIGHER GUSTS. THE DEPRESSION COULD BECOME A TROPICAL STORM LATER TODAY.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1008 MB...29.77 INCHES.


HAZARDS AFFECTING LAND
----------------------
WIND...WINDS NEAR TROPICAL STORM FORCE ARE ALREADY AFFECTING PORTIONS OF THE SOUTHEASTERN BAHAMAS. TROPICAL STORM CONDITIONS WILL GRADUALLY SPREAD OVER THE CENTRAL AND NORTHWESTERN BAHAMAS TONIGHT AND FRIDAY. WEATHER CONDITIONS WILL BEGIN TO DETERIORATE ON THE FLORIDA COAST AND FLORIDA KEYS WITHIN THE WARNING AREA ON FRIDAY.

RAINFALL...THE DEPRESSION IS EXPECTED TO PRODUCE TOTAL RAIN ACCUMULATIONS OF OF 2 TO 4 INCHES OVER SOUTH FLORIDA...WITH POSSIBLE ISOLATED MAXIMUM AMOUNTS OF 5 TO 6 INCHES. RAINFALL AMOUNTS OF 3 TO 5 INCHES ARE EXPECTED OVER THE CENTRAL AND NORTHWEST BAHAMAS...WITH POSSIBLE ISOLATED AMOUNTS OF 5 TO 7 INCHES.

STORM SURGE...STORM SURGE WILL RAISE WATER LEVELS BY AS MUCH AS 1 TO 2 FEET ABOVE GROUND LEVEL OVER PORTIONS OF THE BAHAMAS AND THE FLORIDA KEYS.


NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...200 PM EDT.
NEXT COMPLETE ADVISORY...500 PM EDT.

$$
FORECASTER AVILA/ROBERTS

Tuesday, July 20, 2010

Digital Mode Programs That Work #1: DSCdecoder

DSC stands for Digital Selective Calling. It's an automated mode used with the Global Maritime Distress and Safety System (GMDSS). DSCdecoder is a small, sleek little utility which does exactly what its name promises. It decodes DSC calls, on all three bands (MF, HF, and VHF). These are output to the screen with the MMSI (Maritime Mobile Service Identity) of the calling and called station, plus the message type and any optionally transmitted data such as the reply frequency and mode. You can have the program search over the Internet for the MMSI and substitute it with the station/vessel name, if found.

DSCdecoder is good to just leave going and see what accumulates. DSC is not a busy mode, but it's a fun one to DX. This program does a really nice job of grabbing the real weak stuff.

There's more, though. This program also decodes Navtex (Navigational Telex) and Differential Global Positioning System (DGPS). It does a similarly bang-up job on these. It's the best one of several ham-level programs that I use.

Navtex is a Sitor-B service on three primary frequencies. These are 518 kHz (main freq, nearly always in English), 490 kHz (specific nations and languages, not used in the US), and the more lightly used HF frequency of 4209.5 kHz. The Sitor-B waveform is very close to DSC's (on HF), though other parameters are quite different. Therefore, the decoder performs well on it too. Those who like to tweak things, and who can tune accurately, can set up the advanced decoder. The improvement is slight, but definite.

Navtex stations take turns broadcasting schedules of short, highly formatted, maritime safety and weather messages, from different coastal locations. These rotations typically repeat several times a day, usually every 4 hours. Professional GMDSS equipment keeps a list of headers and typically only prints new messages. Most large vessels will have a Navtex printer somewhere on the bridge.

Navtex is useful for weather forecasts, and it's also fun to DX. Navtex stations are designed for specific local coverage areas, but at night they can propagate amazingly well for this type of station.

The extra dividend is that any Sitor-B decoder that can handle Navtex will work on most other transmissions in this mode. These are all over HF, coming from coast guards and meteo services worldwide.

DGPS is an interesting mode, using minimum-shift keying (MSK). It takes some tuning around in its low band to find strong stations. Fortunately, these are being implemented pretty much worldwide.

Stations use two different baud rates, identifiable from their bandwidth. DGPS decoders for our use turn its packetized data streams into lines of rather cryptic text data. I mostly use this for DXing, and I have checked off an amazing number of DGPS stations, considering that it is designed as anything but a DX mode.

Not many PC programs do DGPS. (Mac users are lucky. They have MultiMode, an excellent program.) Two that do are this one and the no longer supported SkySweeper. I've run them side by side, and most of the time DSCdecoder has successfully recovered more packets.

DSCDecoder is available from www.coaa.uk. The first 21 days are free, so you can try it out, get over a bit of a learning curve, and see if it's for you. After that, it's 25 Euros (a little over 32 bucks at today's exchange).

Tuesday, July 13, 2010

Night of Nights XI Underway

So far nothing from USCG. All other stations active. KKUI is working coast stations on 12552.0.

KLB, the other half of ShipCom with WLO, is s5 here on 8582.5 with a CQ DE KLB marker. Listening on 500 & 8368.0.

Monday, July 12, 2010

Don't Forget Night of Nights XI

I can't believe it's been 11 years since the last stations pulled the plugs on commercial Morse telegraphy in the US.

Be that as it may, this infamous anniversary will once again be marked by several large stations spitting dits and dahs defiantly into the Ether as if nothing had changed. All hail to the Martitime Radio Historical Society for taking the point on this important work.

Period equipment will be used on many frequencies, and ships may call on the receiving frequencies (500 kHz and HF calling Channel 3). KKUI, the restored SS American Victory, has announced its plan to work all stations. They most frequently use the 12 MHz frequency of Channel 3, but others are possible.

The fun starts at the exact time Morse went away, or 0001 UTC on the 13th. Reception reports are welcome, and QSL info is here.

For those in the Bay Area, the receiving station on Point Reyes is open for visitors starting 15 minutes ago. Trust me: it's worth the trip. Directions to the receive site are at the same link. GPS is desirable for navigation, if you have it. The place is really out there.

Here are the frequencies:

KPH
Xmit: 426, 500, 4247.0, 6477.5, 8642.0, 12808.5, 17016.8, 22477.5
Rcv: 500; 4184.0, 6276.0, 8368.0, 12552.0, 16736.0, 22280.5 (C3)

KSM
Xmit: 426, 500, 6474, 8438.3, 12993
Rcv: Same as KPH

KFS
Xmit: 12695.5, 17026.0
Rcv: HF Channel 3 (same as KPH)

WLO
Xmit: 2055.5, 4343.0, 8658.0, 12992.0 and 16968.5
Rcv: 500; 8368 (C3)

NMC (USCG CAMSPAC Pt. Reyes))
Xmit: 448, 472, 500, 6383.0, 8574.0 and 17220.5
Rcv: HF Channel 3 (same as KPH)

NMN (USCG CAMSLANT Chesapeake)
Xmit: 8471.0, 12718.5 and 16976
Rcv: HF Channel 3 (same as KPH)

K6KPH
Simplex 3550, 7050 and 14050 (taking reports)
K6KPH ops use some commercial procedures. DE means about the same as QRZ?

All emission CW Morse telegraphy, and loving it!

Thursday, July 08, 2010

Updated July 12 Night of Nights IX Information

Each year the Maritime Radio Historical Society commemorates 12 July 1999, the date on which the supposed last commercial message was sent in the US. On that date we pick up the thread, keep the faith and maintain the traditions of maritime radio communications so that the skills and traditions of all the radiotelegraphers who came before us will be maintained.

While MRHS station KSM is on the air every Saturday, on Night of Nights we originate stations KPH and KFS in addition to KSM. Other stations join us on the air, this year including KLB, WLO, NMC and NMN.

Flash! The SS AMERICAN VICTORY/KKUI radio department has advised that they will try to work every coast station on the air for Night of Nights XI. KKUI can most often be heard on 12Mc ITU channel 3 (see KPH listing for channel 3 frequencies) but may use other channels as well. If KKUI contacts KPH, KFS or KSM all the transmitters for those stations will be keyed during the contact so listeners will have a good chance of hearing at least the shore side of the exchange.

You can participate by listening or by visiting the ex-RCA receive site to see the action in person. If you'd like to operate K6KPH just bring your key. No license required!

Here are the details of the event:

Date: 12 July 2010 Pacific time, 13 July gmt
Time: 5:01pm Pacific time, 0001 gmt

Station and frequency information (subject to change):

-----

KPH

KPH will transmit on 426, 500, 4247.0, 6477.5, 8642.0, 12808.5, 17016.8 and 22477.5kc.

MF and 22Mc will be on Henry transmitters, rest of KPH HF on 1950s vintage RCA K and L sets.

KPH operators will listen for calls from ships on ITU Channel 3 in all bands. The Channel 3 frequencies are 4184.0, 6276.0, 8368.0, 12552.0, 16736.0 and 22280.5kc on HF and 500kc on MF.

Reception reports may be sent to:

Ms. DA Stoops
P.O. Box 381
Bolinas CA 94924-0381
USA

-----

KFS

KFS will transmit on 12695.5 and 17026.0 -

12695.5 will be on a 1940s vintage Press Wireless PW-15, formerly at the KFS transmitter site in Palo Alto, CA and one of the transmitters on the air on 12 July 1999. 17026.0 will be on a Henry transmitter.

KFS will listen for calls from ships on HF Channel 3 (see KPH listing for frequencies).

Reception reports - same as KPH

Ms. DA Stoops
P.O. Box 381
Bolinas CA 94924-0381
USA

-----

KSM

KSM will transmit on 426, 500, 6474, 8438.3 and 12993kc.

We don't have enough antennas to accommodate the other KSM frequencies when KPH and KFS are on the air. A failure of any of the RCA transmitters may cause a KSM tx to be diverted to cover KPH.

KSM will listen for calls from ships on 500kc and HF Channel 3 (see KPH listing for frequencies).

Reception reports - same as KPH

-----

WLO

WLO will transmit on 2055.5, 4343.0, 8658.0, 12992.0 and 16968.5kc

WLO will listen for calls from HF Channel 3(see KPH listing for frequencies).

Reception reports may be sent to:

WLO Radio
7700 RINLA AVENUE
MOBILE, ALABAMA 36619
USA

-----

KLB

KLB will transmit on 488, 500 (A1 & A2), 8582.5kc

KLB will listen for calls from ships on 500kc and 8368.0kc.

Reception reports - same as WLO

-----

NMC - US Coast Guard Point Reyes, CA

NMC will transmit on 448, 472, 500, 6383.0, 8574.0 and 17220.5kc

NMC will listen for calls from ships on HF Channel 3 (see KPH listing
for frequencies).

Reception reports may be sent to:

Commanding Officer
USCG CAMSPAC
17000 Sir Francis Drake Blvd.
Point Reyes Station, CA 94956-0560
Attn: Operations Specialist in Charge (OSIC)


-----

NMN - US Coast Guard Chesapeake Bay, VA

NMN will transmit on 8471.0, 12718.5 and 16976.0kc

NMN will listen for calls from ships on HF Channel 3 (see KPH listing
for frequencies).

Reception reports may be sent to:

Commanding Officer
USCG CAMSLANT
4720 Douglas A. Munro Rd.
Chesapeake, VA 23322
Attn: Operations Specialist in Charge (OSIC)

-----

K6KPH

Amateur station K6KPH will transmit and listen on 3550, 7050 and 14050kc for KPH, KFS and KSM reception reports.

Professional operators will be at the key and commercial procedures will be used. But please don't hesitate to call, no matter what your code speed or experience level may be.
K6KPH verification reports may be sent to:

Ms. DA Stoops
P.O. Box 381
Bolinas CA 94924-0381
USA

-----

Remember, this is a public event. If you are in the area you are invited to join us at the RCA receive site, 17000 Sir Francis Drake Blvd in the Point Reyes National Seashore north of San Francisco. If using a computer mapping program add "Inverness" after the address above even though the station is well beyond that town.

Doors open at 3:00pm Pacific time. Snacks will be served. Tours of the transmitting station may be arranged for "true believers" by appointment only.

[Plus you can get a piece of Night of Nights cake! -Hugh]


GL de MRHS

Tropical Depression Two Public Advisory #1

000
WTNT32 KNHC 080304
TCPAT2
BULLETIN
TROPICAL DEPRESSION TWO ADVISORY NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022010
1000 PM CDT WED JUL 07 2010

...SECOND TROPICAL DEPRESSION OF THE ATLANTIC SEASON FORMS OVER THE WESTERN GULF OF MEXICO...TROPICAL STORM WARNINGS ISSUED...


SUMMARY OF 1000 PM CDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...23.9N 93.9W
ABOUT 265 MI...425 KM ESE OF BROWNSVILLE TEXAS
ABOUT 245 MI...395 KM E OF LA PESCA MEXICO
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/HR
PRESENT MOVEMENT...NW OR 310 DEGREES AT 14 MPH...22 KM/HR
MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...

A TROPICAL STORM WARNING HAS BEEN ISSUED ALONG THE TEXAS COAST SOUTH OF BAFFIN BAY TO THE MOUTH OF THE RIO GRANDE...AND THE GOVERNMENT OF MEXICO HAS ISSUED A TROPICAL STORM WARNING ALONG THE COAST OF MEXICO FROM RIO SAN FERNANDO TO THE MOUTH OF THE RIO GRANDE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* FROM SOUTH OF BAFFIN BAY TEXAS TO RIO SAN FERNANDO MEXICO

A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED SOMEWHERE WITHIN THE WARNING AREA...IN THIS CASE WITHIN 24 HOURS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA IN THE UNITED STATES...INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST OFFICE. FOR STORM INFORMATION SPECIFIC TO YOUR AREA OUTSIDE UNITED STATES...PLEASE MONITOR PRODUCTS ISSUED BY YOUR NATIONAL METEOROLOGICAL SERVICE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1000 PM CDT...0300 UTC...THE CENTER OF TROPICAL DEPRESSION TWO WAS LOCATED NEAR LATITUDE 23.9 NORTH...LONGITUDE 93.9 WEST. THE DEPRESSION IS MOVING TOWARD THE NORTHWEST NEAR 14 MPH...22 KM/HR... AND THIS GENERAL MOTION ACCOMPANIED BY A SLIGHT DECREASE IN FORWARD SPEED IS EXPECTED FOR THE NEXT 24 HOURS OR SO. ON THE FORECAST TRACK...THE DEPRESSION IS EXPECTED TO MAKE LANDFALL NEAR THE TEXAS-MEXICO BORDER THURSDAY AFTERNOON OR EARLY EVENING.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/HR...WITH HIGHER GUSTS. SOME GRADUAL STRENGTHENING IS FORECAST AND THE DEPRESSION COULD BECOME A TROPICAL STORM BEFORE LANDFALL OCCURS ON THURSDAY.

THE MINIMUM CENTRAL PRESSURE BASED ON NOAA AIRCRAFT RECONNAISSANCE DATA IS ESTIMATED TO BE 1005 MB...29.68 INCHES.


HAZARDS AFFECTING LAND
----------------------
RAINFALL...THE DEPRESSION IS EXPECTED TO PRODUCE TOTAL RAIN ACCUMULATIONS OF 4 TO 8 INCHES OVER PORTIONS OF FAR NORTHEASTERN MEXICO AND COASTAL TEXAS...WITH ISOLATED MAXIMUM AMOUNTS OF 10 INCHES.

WIND...TROPICAL-STORM-FORCE WINDS ARE EXPECTED TO REACH THE COAST WITHIN THE WARNING AREA BY THURSDAY AFTERNOON.


NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...100 AM CDT.
NEXT COMPLETE ADVISORY...400 AM CDT.

$$
FORECASTER STEWART/CANGIALOSI

Air Recon Taskings for TD-2 7-8 July

000
NOUS42 KNHC 061530 COR
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1130 AM EDT TUE 06 JULY 2010
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 07/1100Z TO 08/1100Z JULY 2010
TCPOD NUMBER.....10-036 CORRECTION

I. ATLANTIC REQUIREMENTS
1. SUSPECT AREA (GULF OF MEXICO)
FLIGHT ONE - TEAL 70
A. 07/1800Z
B. AFXXX 01BBA INVEST
C. 07/1600Z
D. 23.0N 91.0W
E. 07/1715Z TO 07/2200Z
F. SFC TO 10,000 FT

FLIGHT TWO - TEAL 71
A. 08/0600, 1200Z
B. AFXXX 0202A CYCLONE
C. 08/0330Z
D. 25.0N 93.5W
E. 08/0445Z TO 08/1200Z
F. SFC TO 10,000 FT

2. SUCCEEDING DAY OUTLOOK: POSSIBLE 3-HRLY FIXES
BEGINNING AT 08/1500Z IF SYSTEM DEVELOPS.
3. REMARKS:
A. TASKING FOR 06/1800Z, 07/0600Z AND 07/1200Z
CANCELED BY NHC AT 06/1210Z.
B. NOAA'S P-3 WILL BEGIN A SERIES OF FOUR RESEARCH
MISSIONS INTO THIS AREA AT 06/2000Z TODAY AND
THEN DEPARTING EVERY 12 HRS. OPERATING ALTITUDE
12,000 FT.

II. PACIFIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. OUTLOOK FOR SUCCEEDING DAY.....NEGATIVE.
JWP


000
NOUS42 KNHC 071600
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1200 PM EDT WED 07 JULY 2010
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 08/1100Z TO 09/1100Z JULY 2010
TCPOD NUMBER.....10-037

I. ATLANTIC REQUIREMENTS
1. SUSPECT AREA (WESTERN GULF)
FLIGHT ONE - TEAL 70
A. 08/1200Z
B. AFXXX 01BBA INVEST
C. 08/0945Z
D. 25.5N 96.5W
E. 08/1100Z TO 08/1700Z
F. SFC TO 10,000 FT

FLIGHT TWO - TEAL 71
A. 08/1800,2100, 09/0000Z
B. AFXXX 0202A CYCLONE
C. 08/1530Z
D. 26.0N 97.0W
E. 08/1730Z TO 09/0000Z
F. SFC TO 10,000 FT

2. SUCCEEDING DAY OUTLOOK.....NEGATIVE.
3. REMARKS:
A. TASKING FOR 07/1800Z, 08/0600Z, AND 08/1200Z
CANCELED BY NHC AT 07/1220Z.
B. NOAA WILL CONDUCT RESEARCH MISSIONS INTO THIS
AREA WITH THE G-IV TAKING OFF AT 07/1730Z AND
A P-3, OPERATING AT 12,000 FT., TAKING OFF AT
07/2000Z AND AGAIN AT 08/0800Z.

II. PACIFIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. OUTLOOK FOR SUCCEEDING DAY.....NEGATIVE.
SEF

Thursday, July 01, 2010

Air Recon Taskings for Hurricane Alex 1 July

000
NOUS42 KNHC 301400
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1000 AM EDT WED 30 JUNE 2010
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 01/1100Z TO 02/1100Z JULY 2010
TCPOD NUMBER.....10-030

I. ATLANTIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. SUCCEEDING DAY OUTLOOK.....NEGATIVE.
3. REMARKS: MISSIONS TASKED FOR HURRICANE
ALEX ON TCPOD 10-029 WILL FLY.

II. PACIFIC REQUIREMENTS
1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
2. OUTLOOK FOR SUCCEEDING DAY.....NEGATIVE.
JWP

HURRICANE ALEX ADVISORY #22

000
WTNT31 KNHC 010237
TCPAT1
BULLETIN
HURRICANE ALEX ADVISORY NUMBER 22
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010
1000 PM CDT WED JUN 30 2010

...ALEX MOVING INLAND OVER NORTHEASTERN MEXICO...

SUMMARY OF 1000 PM CDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...24.3N 97.8W
ABOUT 35 MI...55 KM N OF LA PESCA MEXICO
ABOUT 110 MI...180 KM S OF BROWNSVILLE TEXAS
MAXIMUM SUSTAINED WINDS...100 MPH...160 KM/HR
PRESENT MOVEMENT...W OR 260 DEGREES AT 10 MPH...17 KM/HR
MINIMUM CENTRAL PRESSURE...947 MB...27.96 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...

THE HURRICANE WARNING IS CHANGED TO A TROPICAL STORM WARNING FOR THE COAST OF TEXAS SOUTH OF BAFFIN BAY TO THE MOUTH OF THE RIO GRANDE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A HURRICANE WARNING IS IN EFFECT FOR...
* THE COAST OF MEXICO FROM THE MOUTH OF THE RIO GRANDE TO LA CRUZ

A TROPICAL STORM WARNING IN IN EFFECT FOR...
* THE COAST OF TEXAS FROM THE MOUTH OF THE RIO GRANDE TO PORT
OCONNOR
* THE COAST OF MEXICO SOUTH OF LA CRUZ TO CABO ROJO

FOR STORM INFORMATION SPECIFIC TO YOUR AREA IN THE UNITED STATES...INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST OFFICE. FOR STORM INFORMATION SPECIFIC TO YOUR AREA OUTSIDE UNITED STATES...PLEASE MONITOR PRODUCTS ISSUED BY YOUR NATIONAL METEOROLOGICAL SERVICE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1000 PM CDT...0300 UTC...THE CENTER OF HURRICANE ALEX WAS LOCATED NEAR LATITUDE 24.3 NORTH...LONGITUDE 97.8 WEST. THIS POSITION IS JUST INLAND OF THE COAST OF NORTHEASTERN MEXICO IN THE MUNICIPALITY OF SOTO LA MARINA. ALEX IS MOVING TOWARD THE WEST NEAR 10 MPH...17 KM/HR...AND THIS MOTION IS EXPECTED TO CONTINUE FOR THE NEXT DAY OR SO. ON THIS TRACK...THE CENTER OF ALEX WILL MOVE FARTHER INLAND OVER NORTHEASTERN MEXICO ON THURSDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 100 MPH...160 KM/HR...WITH HIGHER GUSTS. ALEX IS A CATEGORY TWO HURRICANE ON THE SAFFIR-SIMPSON HURRICANE WIND SCALE. STEADY WEAKENING WILL OCCUR AS THE TROPICAL CYCLONE MOVES OVER LAND...AND ALEX IS EXPECTED TO DISSIPATE OVER MEXICO WITHIN 1 TO 2 DAYS.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 35 MILES...55 KM...FROM THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 205 MILES...335 KM.

AN AIR FORCE HURRICANE HUNTER AIRCRAFT REPORTED A MINIMUM CENTRAL PRESSURE OF 947 MB...27.96 INCHES...JUST BEFORE LANDFALL.


HAZARDS AFFECTING LAND
----------------------
RAINFALL...ALEX IS EXPECTED TO PRODUCE TOTAL RAINFALL ACCUMULATIONS OF 6 TO 12 INCHES OVER PORTIONS OF NORTHEASTERN MEXICO AND SOUTHERN TEXAS...WITH ISOLATED MAXIMUM AMOUNTS OF 20 INCHES. THESE RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES... ESPECIALLY OVER MOUNTAINOUS TERRAIN.

WIND...HURRICANE-FORCE WINDS ARE SPREADING INLAND OVER A PORTION OF THE HURRICANE WARNING AREA OVER NORTHEASTERN MEXICO. THESE WINDS WILL DECREASE ON THURSDAY.

STORM SURGE...A DANGEROUS STORM TIDE WILL RAISE WATER LEVELS BY
AS MUCH AS 4 TO 6 FEET ABOVE GROUND LEVEL ALONG THE IMMEDIATE COAST TO THE NORTH OF WHERE THE CENTER HAS MADE LANDFALL. THE WATER COULD PENETRATE INLAND AS FAR AS SEVERAL MILES FROM THE SHORE WITH DEPTH GENERALLY DECREASING AS THE STORM TIDE MOVES INLAND. NEAR THE COAST...THE SURGE WILL BE ACCOMPANIED BY LARGE AND DESTRUCTIVE WAVES. THE STORM TIDE AND WAVES WILL GRADUALLY DIMINISH ON THURSDAY.

TORNADOES...ISOLATED TORNADOES ARE POSSIBLE OVER PORTIONS OF EXTREME SOUTHERN TEXAS OVERNIGHT.


NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...100 AM CDT.
NEXT COMPLETE ADVISORY...400 AM CDT.

$$
FORECASTER PASCH/BERG