[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 241800
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT SUN OCT 24 2010

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST
FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED
ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1745 UTC.

...SPECIAL FEATURE...

TROPICAL STORM RICHARD BECAME A HURRICANE AT 1500 UTC AND IS
LOCATED NEAR 17.1N 87.5W AT 24/1800 UTC. THIS LOCATION IS ABOUT
55 MI...85 KM ESE OF BELIZE CITY...MOVING WNW AT 11 KT.
ESTIMATED MINIMUM CENTRAL PRESSURE IS 988 MB. MAXIMUM SUSTAINED
WIND SPEED IS 75 KT WITH GUSTS TO 90 KT. SEE LATEST NHC
INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS
MIATCPAT4/WTNT34 KNHC AND THE FULL FORECAST/ADVISORY UNDER
AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS.
SCATTERED MODERATE TO STRONG CONVECTION COVERS THE AREA FROM 15N
TO 19N W OF 85W. THE BROAD CYCLONIC CIRCULATION FROM RICHARD IS
ALSO DRAWING DEEP LAYER MOISTURE INTO THE WEST AND NW CARIBBEAN
PRODUCING SIMILAR CONVECTION FROM 10N TO 18N BETWEEN 76W AND
81W. GIVEN THE FAVORABLE CYCLONE STRUCTURE AND
ENVIRONMENT...RICHARD SHOULD CONTINUE TO INTENSIFY BEFORE MAKING
LANDFALL.

...TROPICAL WAVE...

TROPICAL WAVE EXTENDS FROM 24N30W TO 17N35W MOVING NW 10-15 KT.
A WEAK 1011 MB LOW IS EMBEDDED IN THE WAVE AXIS NEAR 20N34W.
WEAK CYCLONIC TURNING IS OBSERVED ABOUT THE AXIS ON SATELLITE
IMAGERY. SCATTERED MODERATE TO ISOLATE STRONG CONVECTION IS FROM
18N-24N BETWEEN 28W-32W. THE WAVE IS LOCATED BETWEEN AN UPPER
RIDGE AND AN UPPER LOW TO THE WEST PROVIDING UPPER LEVEL SHEAR
AND SUPPRESSING ANY FURTHER DEVELOPMENT.

...THE ITCZ...

THE ITCZ AXIS IS ANALYZED FROM THE COAST OF SIERRA LEONE NEAR
8N13W CONTINUING WESTWARD ALONG 5N20W 7N28W 12N34W. THEN...IT
RESUMES NEAR 9N50W TO THE COAST OF GUYANA NEAR 8N59W. A SURFACE
TROUGH IS ANALYZED BETWEEN THE TWO SECTIONS OF THE ITCZ FROM
15N41W TO 8N48W...GENERATING ISOLATED WEAK CONVECTION WITHIN 70
NM EAST OF THE TROUGH AXIS. SCATTERED WEAK TO ISOLATED MODERATE
CONVECTION IS FROM 2N TO 7N BETWEEN 10W AND 30W.

...DISCUSSION...

GULF OF MEXICO...
A BROAD MID-UPPER LEVEL RIDGE OF HIGH PRESSURE COVERS THE FAR
EAST GULF INCLUDING THE FLORIDA PENINSULA AND THE FAR WESTERN
ATLC. THIS FEATURE CONTINUES TO DOMINATE THE AREA OF DISCUSSION
THIS AFTERNOON...PROVIDING SW FLOW ALOFT AND RELATIVELY FAIR
WEATHER CONDITIONS OVER MOST OF THE AREA. MEANWHILE...AN UPPER
LEVEL TROUGH SLOWLY APPROACHES THE NW BASIN WITH A WEAK
JETSTREAK EMBEDDED IN IT ENHANCING SCATTERED WEAK CONVECTION
OVER THE N CENTRAL BASIN N OF 26N BETWEEN 88W AND 91W. SIMILAR
CONVECTION IS OVER THE FAR SE BASIN INCLUDING THE FLORIDA
STRAITS S OF 25N E OF 84W. OTHERWISE...STRONG SUBSIDENCE AND DRY
AIR ALOFT WILL CONTINUE OVER THE NEXT 24 HOURS WITH 15 KT TO 20
KT SURFACE ANTI-CYCLONIC FLOW ACROSS THE GULF.

CARIBBEAN SEA...
HURRICANE RICHARD IS THE PRIMARY CONCERN THIS AFTERNOON...WITH
THE CENTER CURRENTLY MOVING CLOSE TO THE COAST OF BELIZE. SEE
SPECIAL FEATURES ABOVE FOR MORE DETAILS. THE BROAD CYCLONIC
CIRCULATION FROM RICHARD IS ALSO DRAWING DEEP LAYER MOISTURE
INTO THE WEST AND NW CARIBBEAN PRODUCING SIMILAR CONVECTION FROM
10N TO 18N BETWEEN 76W AND 81W. VERY DRY AND STABLE AIR IN
SUBSIDENCE IS ELSEWHERE OUTSIDE THIS AREA OF CONVECTION.
HOWEVER...SOME POSSIBLE SCATTERED LOW LEVEL SHOWERS EMBEDDED IN
THE TRADE WINDS WILL MOVE ACROSS THE AREA THIS AFTERNOON.

ATLANTIC OCEAN...
A BROAD DEEP LAYERED TROUGH MOVES ACROSS THE N CENTRAL ATLC
BASIN AND SUPPORTS A FRONTAL SYSTEM THAT ENTERS THE AREA OF
DISCUSSION AS A SURFACE TROUGH NEAR 32N49W AND CONTINUES SW
ALONG 27N57W TO 25N65W...BECOMING A REMNANT CLOUD/SHEAR LINE TO
25N73W. SCATTERED WEAK CONVECTION IS WITHIN 100 NM ON EITHER
SIDE OF THE SURFACE TROUGH AND SHEAR LINE. A MID LEVEL SHORTWAVE
IS CO-LOCATED WITH THE FRONTAL SYSTEM AND RECENT WATER VAPOR
IMAGERY DATA INDICATES A MID-UPPER LEVEL LOW STARTING TO DEVELOP
WITHIN THE SHORTWAVE NEAR 24N71W. A MID LEVEL ANTI-CYCLONIC
CIRCULATION CENTERED NORTH OF PUERTO RICO IS KEEPING CONDITIONS
FAIR TO THE SE OF THIS SYSTEM. A MID-UPPER LEVEL LOW IS OVER THE
CENTRAL/EAST ATLC SPINNING NEAR 18N41W. THIS FEATURE IS
PRODUCING AN AREA OF MODERATE CONVECTION FROM 19N-24N BETWEEN
34W-38W. THIS AREA OF CONVECTION IS WEST OF THE TROPICAL WAVE
DISCUSSED ABOVE IN THE TROPICAL WAVE SECTION. RECENT SATELLITE
IMAGERY AND LATEST MODEL DATA SUGGEST THAT THIS FEATURE IS
BECOMING MORE APPARENT AT SURFACE LEVEL. THUS...A SURFACE TROUGH
OR WEAK SURFACE LOW COULD BE ANALYZED ON THE FOLLOWING SURFACE
ANALYSES. A SURFACE RIDGE DOMINATES THE E ATLC N OF 24N E OF 40W
ANCHORED BY A 1029 MB HIGH E OF THE AZORES.

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$

GARCIA



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