Caribbean - Central America Weather

[cycloneye]

Well, the weather is ok in St Lucia but just as I was thinking of drifting off to sleep around midnight, we had an earthquake - 5.1, small beer maybe but the strongest here for a while. It was actually off island, maybe 40 miles away but not too deep so strong enough for us to shake, rattle and roll. Also felt in St Vincent and Martinique.

Reactions range from slight to strong on the MMI scale - 3 to 5.

With forcecasts suggesting a ramping up over the Atlantic in the coming days, I think I'll have to go buy that tin helmet!

The information about the quake is posted at geology forum.

viewtopic.php?f=67&t=107389&st=0&sk=t&sd=a&start=100

[msbee]

Barbara, here the link for that image amd more images and loops.

http://www.srh.noaa.gov/sju/?n=satellite01

Thanks Luis
I keep losing my bookmarks.
Have a good Sunday!
Barbara

[Macrocane]

Hi! Yesterday temps in Central America:
-Near normal lows in most of the region, except for Quetzaltenango (cooler than normal) and San Miguel (warmer than normal).
-Warmer than normal highs in all the region except for Honduras and the higher elevations of Costa Rica and Panama (Irazu, Boquete).

Minimum Temperatures
Belize city, Belize 26°C (79°F)
Mountain Pine Ridge, Belize 20.6°C (69.1°F)
Guatemala city, Guatemala 17°C (63°F)
Quetzaltenango, Guatemala 5.7°C (42.3°F)
Zacapa, Guatemala 23°C (73°F)
San Salvador, El Salvador 20.4°C (68.7°F)
Las Pilas, El Salvador 11.4°C (52.5°F)
San Miguel, El Salvador 24.3°C (75.7°F) Warmest since June 14
Tegucigalpa, Honduras 17°C (63°F)
La Esperanza, Honduras 15°C (59°F)
Choluteca, Honduras 25°C (77°F)
Managua, Nicaragua 25°C (77°F)
Jinotega, Nicaragua 21°C (70°F)
San Jose, Costa Rica 18.7°C (65.7°F)
Liberia, Costa Rica 22.2°C (72.0°F)
Irazu volcano, Costa Rica 5.9°C (42.6°F)
Panama city, Panama 23.4°C (74.1°F)
Boquete, Panama 14.5°C (58.1°F)

Maximum Temperatures
Belize city, Belize 32°C (90°F)
Mountain Pine Ridge, Belize 30.6°C (87.1°F)
Guatemala city, Guatemala 27°C (81°F)
Quetzaltenango, Guatemala 23.6°C (74.5°F) Warmest since July 6
Zacapa, Guatemala 34°C (93°F)
San Salvador, El Salvador 30.7°C (87.3°F)
Las Pilas, El Salvador 21.1°C (70.0°F)
San Miguel, El Salvador 35.8°C (96.4°F)
Tegucigalpa, Honduras 28°C (82°F)
La Esperanza, Honduras 23°C (73°F)
Choluteca, Honduras 35°C (95°F)
Managua, Nicaragua 33°C (91°F)
Jinotega, Nicaragua 27°C (81°F)
San Jose, Costa Rica 29.0°C (84.2°F)
Liberia, Costa Rica 32.0°C (89.6°F)
Irazu volcano, Costa Rica 11.7°C (53.1°F)
Panama city, Panama 35.2°C (95.4°F) Warmest since June 13
Boquete, Panama 20.9°C (69.6°F)

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
245 PM AST SUN AUG 7 2011

.SYNOPSIS...TUTT LOW OVER HISPANIOLA WILL CONTINUE TO RETROGRESS
TOWARD THE WRN CARIBBEAN WHILE SUBTROPICAL RIDGE BUILDS NORTH OF
THE REGION. TROPICAL WAVE NEAR 50W WILL REACH THE LOCAL AREA WED
NIGHT.


&&

.DISCUSSION...A DRIER AND MORE STABLE AIR MASS WILL ESTABLISH FOR THE
FIRST PART OF THE WEEK AS SUBTROPICAL RIDGE BUILDS NORTH OF THE
REGION. NEXT TROPICAL WAVE NEAR 50W THIS AFTERNOON POISED TO MOVE
ACROSS THE AREA WED NIGHT WITH INCREASES CHANCES FOR
PRECIPITATION. WAVE HAS MODERATE SPIN AND AN ELONGATED SFC
CIRCULATION AS SEEN ON MORNING ASCAT PASS BUT LACKS DEEP
CONVECTION. NONE OF THE GLOBAL MODELS INDICATE DEVELOPMENT OF THIS
WAVE INTO A TC BUT ALL WAVES ESPECIALLY IN AUGUST ARE WORTH
MONITORING. NEXT WAVE NEAR 20W (INVEST 92L) IS ABOUT 8 DAYS FROM
REACHING THE LOCAL AREA HAS PLENTY OF SPIN AND DEEP CONVECTION.
THIS ONE IS A GOOD CANDIDATE FOR TC DEVELOPMENT. STILL PLENTY OF
TIME TO SEE HOW THIS WAVE EVOLVES.


&&

.AVIATION...VFR CONDITIONS NEXT FEW DAYS WITH JUST ISOLD/SCT
AFTERNOON CONVECTION OUT WEST. NEXT TROPICAL WAVE WED NIGHT WITH
INCREASES CHANCES FOR TSTMS ESPECIALLY ERN PR...USVI AND LEEWARD
ISLANDS TERMINALS.


&&

.MARINE...SEAS UP TO 6 FT OFFSHORE BUT SUBSIDING DOWN OVR THE
NEXT FIVE DAYS.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 80 90 79 89 / 20 20 20 20
STT 79 83 79 83 / 40 40 30 30

[cycloneye]

Good morning.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
441 AM AST MON AUG 8 2011

.SYNOPSIS...HIGH PRESSURE CONTINUES TO THE NORTH OF THE LOCAL
AREA. AVAILABLE MOISTURE IS EXPECTED TO SLIGHTLY DECREASE ON
TUESDAY AND THEN INCREASE ON WEDNESDAY TO THURSDAY. MODELS STILL
INSISTING IN TROPICAL WAVE OVER THE AREA FOR WEDNESDAY NIGHT INTO
THURSDAY MORNING.

&&

.DISCUSSION...AS THE SUBTROPICAL RIDGE PERSISTS TO THE NORTH OF
THE LOCAL AREA...A SOMEWHAT DRIER AND MORE STABLE AIR MASS SHOULD
PERSIST OVER THE AREA FOR THE NEXT FEW DAYS. HOWEVER...FORECAST
SOUNDINGS STILL SUGGEST SOME INSTABILITY AND MOISTURE IN THE
AREA...SO THERE IS STILL A CHANCE OF SHOWERS AND THUNDERSTORMS DUE
TO DAYTIME HEATING AND LOCAL EFFECTS.

THERE IS A WEAK TROPICAL WAVE AROUND 60W. HOWEVER...NONE OF THE
MODELS DEVELOP IT INTO A TROPICAL CYCLONE AND THE MODELS ARE
INSISTING THAT THE BULK OF THE MOISTURE WILL STAY TO OUR SOUTH
UNTIL ANOTHER TROPICAL WAVE APPROACHES THE AREA ON WEDNESDAY NIGHT
AND THURSDAY MORNING...BRINGING MORE MOISTURE AND INSTABILITY TO
THE LOCAL AREA. ACCORDING TO GFS...PW VALUES WOULD INCREASE FROM
1.35 ON TUESDAY AT 18Z TO 1.7 ON WEDNESDAY AT 18Z TO 2.1 ON
THURSDAY AT 18Z.

NAAPS FORECASTS ALSO SUGGEST SOME CONCENTRATION OF DUST UNTIL
WEDNESDAY NIGHT INTO THURSDAY MORNING...WITH THE APPROACH OF THE
AFOREMENTIONED TROPICAL WAVE.

&&

.AVIATION...VFR CONDITIONS EXPECTED ACROSS ALL SITES THROUGH 17Z.
MVFR CONDITIONS IN VCNTY OF TJMZ AND TJBQ AIRPORTS FROM 17-22Z
WITH LOWER CIGS AND VCNTY THUNDERSTORMS. WINDS PREDOMINIATELY
EASTERLY AT 10 TO 15 KNOTS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 90 78 89 80 / 20 20 20 20
STT 89 79 89 79 / 30 20 20 30

[cycloneye]

Discussion from Rob of Crown Weather Services about what to expect in the Atlantic in the next 1-2 weeks.

http://www.crownweather.com/?page_id=4557

[Gustywind]

Patches of moderate convection affecting Guadeloupe since this morning...

[Macrocane]

Hi! Yesterday in Central America:
-Warmer than normal lows were registered in all the region, except El Salvador where near normal lows were exprienced.
-Warmer than normal highs were registered in all the region, only Belize and Panama had near normal highs.

Minimum Temperatures
Belize city, Belize 28°C (82°F)
Mountain Pine Ridge, Belize 22.3°C (72.1°F)
Guatemala city, Guatemala 18°C (64°F)
Quetzaltenango, Guatemala 9.5°C (49.1°F)
Zacapa, Guatemala 23°C (73°F)
San Salvador, El Salvador 20.0°C (68.0°F)
Las Pilas, El Salvador 12.7°C (54.9°F)
San Miguel, El Salvador 23.4°C (74.1°F)
Tegucigalpa, Honduras 20°C (68°F)
La Esperanza, Honduras 15°C (59°F)
Choluteca, Honduras 24°C (75°F)
Managua, Nicaragua 25°C (77°F)
Jinotega, Nicaragua 21°C (70°F)
San Jose, Costa Rica 18.6°C (65.5°F)
Liberia, Costa Rica 23.1°C (73.6°F)
Irazu volcano, Costa Rica 5.4°C (41.7°F)
Panama city, Panama 24.3°C (75.7°F)
Boquete, Panama 14.2°C (57.6°F)

Maximum Temperatures
Belize city, Belize 32°C (90°F)
Mountain Pine Ridge, Belize 29.8°C (85.6°F)
Guatemala city, Guatemala 26°C (79°F)
Quetzaltenango, Guatemala 22.2°C (72.0°F)
Zacapa, Guatemala 34°C (93°F)
San Salvador, El Salvador 30.9°C (87.6°F)
Las Pilas, El Salvador 22.0°C (71.6°F)
San Miguel, El Salvador 36.1°C (97.0°F)
Tegucigalpa, Honduras 29°C (84°F)
La Esperanza, Honduras 24°C (75°F)
Choluteca, Honduras 34°C (93°F)
Managua, Nicaragua 33°C (91°F)
Jinotega, Nicaragua 26°C (79°F)
San Jose, Costa Rica 30.6°C (87.1°F) Warmest since June 30
Liberia, Costa Rica 33.5°C (92.3°F)
Irazu volcano, Costa Rica 14.6°C (58.3°F)
Panama city, Panama 31.0°C (87.8°F)
Boquete, Panama 22.9°C (73.2°F)

[cycloneye]

There was a moderate quake this morning with epicenter just NNE of Barbados. See the details at the Eastern Caribbean Seismic Activity thread at geology forum.

viewtopic.php?f=67&t=107389&p=2157447#p2157447

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
258 PM AST MON AUG 8 2011

.SYNOPSIS...SURFACE HIGH ACROSS THE ATLANTIC WILL MAINTAIN GENTLE
TO MODERATE TRADE WINDS ACROSS THE REGIONAL WATERS. THE NEXT
TROPICAL WAVE WILL ENTER THE EASTERN CARIBBEAN ON WEDNESDAY.

&&

.DISCUSSION...AFTER A VERY ACTIVE DAY AFFECTED THE WESTERN AND
NORTHWEST SECTION OF PUERTO RICO YESTERDAY...A VERY DRY AIR MASS
HAS MOVED ACROSS THE REGION FROM THE NORTHEAST. THIS HAS LIMITED
THE DEVELOPMENT OF SHOWERS TODAY...WITH ONLY ISOLATED SHOWERS
NOTED MAINLY ACROSS THE WESTERN PART OF PUERTO RICO IN THE VICINITY
OF MAYAGUEZ. THIS WEATHER PATTERN IS EXPECTED TO PREVAIL TO AT
LEAST TUESDAY NIGHT...WITH LATEST GUIDANCE SUGGESTING PW VALUES
WILL REMAIN NEAR 1.5 INCHES...AND THETA-E VALUES REMAINING NEAR
325K AT 700MB..WHICH..AT THE TROPICS...IS ESSENTIALLY DRY. BY
WEDNESDAY...THETA -E VALUES WILL INCREASE...IN TANDEM WITH AN
APPROACHING TROPICAL WAVE WHICH WAS LOCATED LATE THIS AFTERNOON
EAST OF THE LESSER ANTILLES. THEREFORE...EXPECTED AN INCREASE IN
SHOWERS AND THUNDERSTORMS BY WEDNESDAY AND THURSDAY...WITH
COMPUTER MODELS SUGGESTING DRIER AIR MOVING IN ONCE AGAIN BY
FRIDAY AND THROUGHOUT THE WEEKEND. NO SIGNIFICANT WEATHER EVENTS ARE
FORECAST TO AFFECT THE LOCAL REGION IN THE LONG TERM.

&&

.AVIATION...VFR CONDS CONT ALL TAF SITES XCPT PSBL CIGS THIS
AFTERNOON AND AGAIN TUE AT TJSJ/TJBQ IN SHRA/TSRA. FEW MTN OBSCR
WEST PR DURING THESE AFTERNOON PERIODS. WIND BLO FL200 E 10-15 KTS
XCPT UP TO 20 KTS LATE TONIGHT.



&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 79 90 80 90 / 20 20 20 30
STT 78 89 81 90 / 20 20 30 30

[Rgv20]

Do not know if our friend Macrocane has been following the long range GFS but it looks like Central America is going to turn very rainy starting by the end of next week.


The GFS Ensembles have some impressive negative 500mb anomalies for Central America, Southern Mexico, and all of the Caribbean. This pattern would suggest very heavy rain and maybe a tropical disturbance taking shape.

[Macrocane]

Yep, Thanks Rgv20! I've been looking at the models and it seems that the wettest days will start in about 10 days as you mentioned it, it is still in the long range so it could change though, several weeks ago the models showed a very strong monsoon trough over the region but at the end it was not that strong and thankfully the rains were less than expected. Anyway it worths watching and this time could verify so I'll be monitoring it. By the way, where did you get those graphics? I will bookmark it. Thanks again.

[Rgv20]

Yeah, very very long range but something to keep an eye on, forgot to mention that the GFS has the backing of the Euro Ensembles as far as the 500mb anomalies.

Here is the link http://www.esrl.noaa.gov/psd/map/images/ens/ens.html

[cycloneye]

Good morning.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
434 AM AST TUE AUG 9 2011

.SYNOPSIS...SURFACE HIGH ACROSS THE ATLANTIC WILL MAINTAIN GENTLE
TO MODERATE TRADE WINDS ACROSS THE REGIONAL WATERS. THE NEXT
TROPICAL WAVE IS EXPECTED ACROSS THE AREA ON WEDNESDAY
AFTERNOON...WITH MOISTURE LINGERING UNTIL FRIDAY.

&&

.DISCUSSION...THE RELATIVELY DRY AIR IS EXPECTED TO CONTINUE
ACROSS THE AREA TODAY BEFORE A TROPICAL WAVE REACHES OUR
AREA ON WEDNESDAY...WITH THE ASSOCIATED MOISTURE LINGERING AROUND
UNTIL FRIDAY. EVEN THOUGH THERE IS RELATIVELY DRY AIR OVER OUR
AREA TODAY...THERE IS SOME INSTABILITY AND ENOUGH MOISTURE TO HAVE
AN ISOLATED THUNDERSTORM OUR TWO...MAINLY ACROSS THE WESTERN SECTIONS
OF PR.

THERE IS SOME DISCREPANCY BETWEEN MODELS WHEN IT COMES TO THE
AVAILABLE MOISTURE FOR THE NEXT FEW DAYS. THE GFS MODEL IS DRIER
THAN THE NAM12 IN ITS FORECAST SOUNDINGS STARTING ON WEDNESDAY AT
06Z. IT SEEMS AS THOUGH THE GFS HAS THE APPROACHING WAVE A BIT
MORE TO THE SOUTH THAN THE NAM12 DOES FOR THE SAME TIME PERIOD.
EITHER WAY...BOTH MODELS SUGGEST A SIGNIFICANT INCREASE IN
MOISTURE STARTING ON WEDNESDAY AFTERNOON UNTIL FRIDAY...INCREASING
THE CHANCES FOR SHOWERS AND THUNDERSTORMS ACROSS THE LOCAL
ISLANDS...ESPECIALLY IN THE AFTERNOONS ACROSS WESTERN PR WHEN
COMBINED WITH THE LOCAL EFFECTS. ONCE THIS WAVE PASSES...THE
COMPUTER MODELS ARE SUGGESTING DRIER AIR MOVING IN LATE FRIDAY OR
EARLY SATURDAY AND KEEPING THE RELATIVELY DRIER AIR ACROSS THE
AREA UNTIL SUNDAY.

AT THE PRESENT TIME THERE IS NO TROPICAL CYCLONE FORMATION
EXPECTED DURING THE NEXT 48 HOURS ACROSS THE ATLANTIC.

&&

.AVIATION...VFR CONDITIONS EXPECTED ACROSS ALL SITES THROUGH 17Z.
MVFR CONDITIONS IN VCNTY OF TJMZ AND TJBQ AIRPORTS FROM 17-22Z
WITH LOWER CIGS AND VCNTY THUNDERSTORMS. WINDS PREDOMINIATELY
EASTERLY AT 10 TO 15 KNOTS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 90 79 89 80 / 10 0 40 20
STT 89 81 90 80 / 20 20 30 40

[Gustywind]

Wet and humid weather conditions should continue on East Carib

[Gustywind]

- Updates from the Islands -
- - Dominica - -
- Grey, dark heavy showers

•By Lisette Stevens <jaco.lass at gmail.com>
•Date: Tue, 9 Aug 2011 05:44:13 -0700
http://stormcarib.com/reports/current/dominica.shtml


We have had dreadful rain all night and downpours this morning! It looks like we are going to get even more wet weather coming behind this splodge! All we want is some sunshine we are in the Caribbean, yes, it is hurricane season but please let's have some lovely weather in between! Jaco Ladd and I are originally from the UK. We are appalled by the riots that are happening in the London. It seems there is unrest all over the world because of this terrible financial melt down. What was that Bob Dylan song? the Times they are a Changing! We in our peaceful island Dominica have seen some changes recently, it is very upsetting.

[Gustywind]

Latest weather situation in Guadeloupe
http://www.microsofttranslator.com/bv.a ... 133890.php

METEO

Yellow vigilance even for heavy rain and thunderstorms

franceantilles.fr08.08.2011

A very moist and unstable air mass is bulging and is maintained at the level of our latitudes at the front of a tropical wave expected Tuesday night to Wednesday.

Today, a few thunderstorms crossed the archipelago, causing heavy rains but not significant accumulations of precipitation. That night, showers continue to occur. They are usually brief but stormy risk persists. Tomorrow Tuesday, stormy showers resumed. The more exposed areas lie in the mountains and on an axis ranging from the great funds to Deshaies in
passing through Gosier, Pointe-à-Pitre, Baie-Mahaut, Lamentin and Sainte Rose as well as in the bag codends.
On the night of Tuesday to Wednesday, a tropical wave turn Guadeloupe enhancing thunderstorm activity and rain. This time persists in Wednesday. Despite a relative calm this evening, vigilance is maintained as thunderstorm activity and the rains are likely to resume tomorrow before the passage of the wave itself.
Risk of lightning strikes, floods or raw fast especially close to rivers, ravines, Fords and usually flood areas. If the rollups are becoming too important, risks of landslides.

[Macrocane]

Hi! Yesterday temps in Central America:
-Cooler than normal lows were registered in Honduras. The lows were warmer than normal in Costa Rica and Guatemala. They were near normal in the rest of the region.
-Warmer than normal highs were registered in Guatemala, Honduras, Nicaragua and Costa Rica. Near normal lows occurred in Belize El Salvador and Panama.

Minimum Temperatures
Belize city, Belize 26°C (79°F)
Mountain Pine Ridge, Belize 21.6°C (70.9°F)
Guatemala city, Guatemala 18°C (64°F)
Quetzaltenango, Guatemala 9.2°C (48.6°F)
Zacapa, Guatemala 25°C (77°F)
San Salvador, El Salvador 20.4°C (68.7°F)
Las Pilas, El Salvador 12.2°C (54.0°F)
San Miguel, El Salvador 23.0°C (73.4°F)
Tegucigalpa, Honduras 16°C (61°F)
La Esperanza, Honduras 12°C (54°F) Coolest since May 23
Choluteca, Honduras 23°C (73°F)
Managua, Nicaragua 23°C (73°F)
Jinotega, Nicaragua 20°C (68°F)
San Jose, Costa Rica 19.2°C (66.6°F) Warmest since June 28
Liberia, Costa Rica 23.6°C (74.5°F)
Irazu volcano, Costa Rica 6.1°C (43.0°F)
Panama city, Panama 22.9°C (73.2°F)
Boquete, Panama 12.7°C (54.9°F)

Maximum Temperatures
Belize city, Belize 32°C (90°F)
Mountain Pine Ridge, Belize 30.5°C (86.9°F)
Guatemala city, Guatemala 27°C (81°F)
Quetzaltenango, Guatemala 23.9°C (75.0°F) Warmest since May 28
Zacapa, Guatemala 35°C (95°F)
San Salvador, El Salvador 29.7°C (85.5°F)
Las Pilas, El Salvador 22.3°C (72.1°F)
San Miguel, El Salvador 35.1°C (95.2°F)
Tegucigalpa, Honduras 30°C (86°F) Warmest since June 12
La Esperanza, Honduras 25°C (77°F)
Choluteca, Honduras 35°C (95°F)
Managua, Nicaragua 33°C (91°F)
Jinotega, Nicaragua 28°C (82°F)
San Jose, Costa Rica 28.7°C (83.7°F)
Liberia, Costa Rica 31.7°C (89.1°F)
Irazu volcano, Costa Rica 17.8°C (64.0°F)
Panama city, Panama 31.2°C (88.2°F)
Boquete, Panama 23.3°C (73.9°F)

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
312 PM AST TUE AUG 9 2011

.SYNOPSIS...HIGH PRESSURE RIDGE NORTH OF THE REGION WILL CONTINUE TO
INFLUENCE THE WEATHER PATTERN THROUGH AT LEAST LATE WEDNESDAY.
TROPICAL WAVE ALONG 55W WILL MOVE THROUGH THE LESSER ANTILLES WED
AND MOVE OVER THE FORECAST AREA EARLY THU AND FRI ACROSS THE CENTRAL
CARIBBEAN.

&&

.DISCUSSION...BLENDED TPW AND GPS-MET OBS SYSTEM INDICATED THAT
THE PRECIPITABLE WATER VALUES HAVE FALLEN BELOW 1.5 INCHES THIS
AFTERNOON AND ARE NOT EXPECTED TO MAKE A SIGNIFICANT RECOVERY
BEFORE THURSDAY. ALTHOUGH THE HIGH PRESSURE RIDGE OVER THE SW
NORTH ATLANTIC TEND TO WEAKEN DURING THE NEXT DAY OR TWO... STRONG
LOW LEVEL CAP WILL PERSIST THROUGH THE FORECAST AREA...LIMITING
ANY SIGNIFICANT CONVECTIVE ACTIVITY ACROSS THE LOCAL ISLANDS.
MODELS CONTINUE TO SHOW THE ARRIVAL OF THE NEXT TROPICAL WAVE ON
THURSDAY. UNDER INFLUENCE OF THE WAVE...MOISTURE WILL THEN START
TO SURGE EARLY THURSDAY MORNING...WITH A PWAT MAXIMA SOUTH OF
PUERTO RICO EXPECTED THURSDAY AFTERNOON. UNLESS ECHO TRAINING
ESTABLISHES...DO NOT THINK THE SHOWER ACTIVITY IS GOING TO BE AS
INTENSE AS SOME OF THE GUIDANCE SUGGESTS (HIGH RESOLUTION WRF IN
PARTICULAR). BUT...AS SATURATED AS THE TERRAIN IS IT IS NOT GOING
TO TAKE MUCH TO FAVOR FLOODING ACROSS PORTIONS OF PUERTO RICO.

&&

.AVIATION...VFR CONDS WILL CONTINUE TO PREVAIL ACROSS THE FORECAST
PERIOD. FEW MTN OBSCR WEST PR PSBL DURING THE AFTERNOON HOURS. EASTERLY
WINDS AT 15 KTS OR LESS BLW 5 KFT.

&&

.MARINE...EAST NORTHEAST TRADE WIND FLOW OF 10-15 KNOTS WILL
CONTINUE THROUGH WEDNESDAY NIGHT...BECOMING EAST SOUTHEAST ON
THURSDAY AS THE WAVE PASSES. SEAS OF 1 TO 3 FEET ARE MAINLY
EXPECTED...ALTHOUGH BRIEF 4 FOOT SEAS ARE POSSIBLE ACROSS THE
OFFSHORE ATLANTIC WATERS. WINDS AND SEAS WILL LIKELY REMAIN
BELOW SMALL CRAFT ADVISORY LEVELS THROUGH THE WEEKEND.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 79 89 80 90 / 0 40 20 40
STT 81 90 80 89 / 20 30 20 30

[cycloneye]

Good morning.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
348 AM AST WED AUG 10 2011

.DISCUSSION...
I THOUGHT THE MODELS...ESPECIALLY THE NAM12 DID A GOOD JOB
FORECASTING THE INCREASE IN THETA-E`S YESTERDAY AFTERNOON AND
EVENING AS SHOWERS HAVE INCREASED ACROSS THE AREA COMPARED TO THE
PREVIOUS TWO NIGHTS THIS IS BEING SHOWN QUITE WELL ON BLENDED
TOTAL PRECIPITABLE WATER VALUES WITH LOWER VALUES JUST SOUTH OF
OUR FORECAST AREA.

THE STRENGTH OF THE MID-UPPER LEVEL HIGH PRESSURE SYSTEM THAT HAS BEEN
KEEPING A CAP ON THE LOCAL AREA STARTED TO ERODE TONIGHT IN
RESPONSE TO A SHORTWAVE WHICH WILL BE MOVING OVER THE TOP DURING
THE NEXT 24-36 HOURS. TUTT TROUGHING JUST EAST OF THE AREA
SHOWING UP WITH A COUPLE OF MINOR VORT CENTERS...ONE NEAR 19N60W
THE OTHER NEAR 20N50W EVIDENCE THAT THE HIGH IS BEING EATEN AWAY
FROM BOTH SIDES. GUIDANCE SUGGESTS NET DECREASE IN MID LEVEL
HEIGHTS THROUGH NEXT 48 HOURS.

I BELIEVE WE WILL BE DEALING WITH TWO DIFFERENT ENTITIES NEXT
24-36 HOURS. THE FIRST IS A TROPICAL WAVE LOCATED NEAR 60W THIS
MORNING THAT SHOULD CONTINUE TO MOVE WEST AT AROUND 15 MPH AND
PASS MAINLY SOUTH OF THE AREA THROUGH TODAY...THE SECOND IS THE
REFLECTION OF THE TUTT WITH SHOULD MOVE ACROSS THE AREA LATE
TONIGHT. THIS WOULD HELP EXPLAIN THE SHIFT OF THE WINDS TO THE
NORTHEAST YESTERDAY AND THE FORECAST SHORT DURATION SHIFT TO THE
SOUTHEAST TODAY....WITH A SHARPER SHIFT IN THE WINDS EXPECTED ON
THURSDAY AS THE STRONGER MID-LEVEL REFLECTION OF THE TUTT MOVES
THROUGH WITH RAPID DROPS IN MID LEVEL TEMPS AND A SHIFT TO DEEP
EASTERLIES ACROSS THE FORECAST AREA. MODELS DO HAVE A DIFFERENT
TAKE ON TIMING FOR THE UPPER TROUGH WITH GFS MOVING A BIT FASTER
IN FIRST 18 HOURS AND SLOWER MOVING OUT...WITH THE NAM12 A LITTLE
BIT SLOWER TO GET HERE BUT MUCH FASTER TO GET IT OUT...HOWEVER
BOTH A PRETTY CONSISTENT THAT THE AXIS WILL PASS OVERHEAD BETWEEN
00Z AND 06Z TONIGHT.

FROM WHAT I CAN TELL FROM SATELLITE BELIEVE THAT GFS SOLUTION IS
REASONABLE ESPECIALLY WHEN COMPARING LOWER LEVEL EQUIVALENT
POTENTIAL TEMPERATURE WITH BLENDED TROPICAL PRECIPITABLE WATER.
LOOK FOR A DECREASE THIS MORNING AS A "DRY SLOT" MOVES ACROSS US
WITH AN INCREASE IN MOISTURE FLUX MAGNITUDE AROUND THE TIME OF
MAXIMUM AFTERNOON HEATING. BOTH NAM12 AND GFS BOTH SHOW BEST LOW-
MID LEVEL OMEGA VALUES THIS AFTERNOON ALTHOUGH EXACT LOCATION
DIFFERS A TAD.

WITH ALL OF THIS SAID AND DONE...WILL LIKELY BUMP THE POPS UP
HIGHER ACROSS WESTERN PUERTO RICO. BELIEVE THERE WILL BE PLENTY OF
SUNSHINE THIS MORNING AND WITH THE EXPECTED INCREASE OF MOISTURE
BELIEVE WE WILL WILL GET MORE PRECIP THAN EARLIER EXPECTED.

A FAR AS THE TROPICS GO...GFS REALLY JUMPED ON TWO WAVES WITH BOTH
PULLING NORTH BEFORE REACHING 60W. THE FIRST EARLY SUNDAY MORNING
THE SECOND MUCH STRONGER FOLLOWING THE SAME PATH NEXT WEDNESDAY OR
THURSDAY. STILL TO EARLY TO SAY WITH ANY CERTAINTY WHAT WILL
HAPPEN...IF ANYTHING...TO THESE WAVES.

&&

.AVIATION...VFR CONDITIONS WILL PREVAIL ACROSS ALL TAF SITES
OVERNIGHT...WITH ISOLATED PASSING SHOWERS POSSIBLE IN AND AROUND
TJSJ/TIST/TISX AND TNCM/TKPK THROUGH ABOUT 10/16Z. AFT 10/16Z...
MVFR...OR EVEN TEMPO IFR CONDITIONS ARE POSSIBLE ACROSS THE
CORDILLERA CENTRAL AND WESTERN PUERTO RICO IN
SHRA/TSRA...INCLUDING TJMZ AND TJBQ. LLVL WINDS WILL BE MAINLY
FROM THE EAST SOUTHEAST AT 5 TO 15 KTS.

&&

.MARINE...SEAS SHOULD REMAIN IN THE 2-5 FOOT RANGE THROUGH THE
REST OF THIS WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 89 80 90 79 / 40 20 40 20
STT 90 80 89 80 / 30 20 30 30