[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 301751
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST SAT JAN 30 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.

...THE ITCZ...
THE ITCZ AXIS IS CENTERED FROM THE SOUTHERN SIERRA LEONE COAST
NEAR 7N12W CONTINUING WESTWARD ALONG 4N20W 3N30W 2N40W TO THE
NORTHEAST BRAZIL COAST NEAR EQ50W. SCATTER MODERATE TO STRONG
CONVECTION IS COVERING AND GREAT PORTION OF THE CENTRAL
ITCZ...FROM 3S TO 5N BETWEEN 22W AND 35W. THIS BROAD AREA OF
CONVECTION WILL CONTINUE TO MOVE WESTWARD NEAR THE NORTHEAST
BRAZIL COAST OVER THE NEXT 24 HOURS.

...DISCUSSION...

GULF OF MEXICO...
A COLD FRONT EXTENDS ACROSS THE EASTERN...CENTRAL...AND SOUTHERN
GULF OF MEXICO. A 1008 MB LOW SUPPORTING THIS FRONT IS OVER
SOUTH CENTRAL GEORGIA...SLOWLY MOVING INTO THE WESTERN ATLANTIC
OCEAN. THE FRONT IS ANALYZED ALONG 30N83W 26N86W 23N90W 19N92W.
DOPPLER RADAR IMAGERY SHOWS A LINE OF HEAVY SHOWERS AND
THUNDERSTORMS ALONG THE FRONT...WITH SHOWERS EXTENDING FURTHER
80 NM EAST OF THE FRONT. THE MAIN AREA OF PRECIPITATION IS
CURRENTLY CROSSING THE CENTRAL FLORIDA PENINSULA FROM 27N TO
30N. AN UPPER LEVEL SHORTWAVE OVER LOUISIANA IS SUPPORTING THIS
LOW PRESSURE SYSTEM. SATELLITE WATER VAPOR IMAGERY SHOWS MID TO
UPPER LEVEL MOISTURE FROM THE EASTERN TROPICAL PACIFIC MOVING
ACROSS MEXICO INTO THE GULF...THIS FEATURE IS BRINGING A WARM
AND MOIST UPPER LEVEL AIRMASS ACROSS MUCH OF THE REGION. SURFACE
OBSERVATIONS ACROSS THE FLORIDA PENINSULA SHOW SOUTHERLY FLOW 15
TO 20 KT AHEAD OF THE FRONT. SHIP AND OIL PLATFORM OBSERVATIONS
ACROSS THE GULF SHOW NORTHWEST WINDS 20 TO 25 KT BEHIND THE COLD
FRONT. GALE FORCE WINDS ARE CURRENTLY OVER THE SOUTHERN
GULF...SOUTH OF 22N WEST OF 94W. WINDS IN THIS AREA ARE EXPECTED
TO DECREASE BELOW GALE FORCE CRITERIA OVER THE NEXT 12 HOURS.
THE FRONT WILL CONTINUE TO MOVE EASTWARD WITH CONVECTION AHEAD
OF IT. IN 24 HOURS THE FRONT IS EXPECTED TO CONTINUE TO MOVE
ACROSS THE FLORIDA PENINSULA INTO THE WESTERN ATLANTIC
OCEAN...LEAVING A COOL AND DRY AIRMASS OVER THE GULF AND FLORIDA
PENINSULA.

CARIBBEAN SEA...
UPPER LEVEL RIDGE OF HIGH PRESSURE DOMINATES MOST OF THE
CARIBBEAN SEA. THIS FEATURE IS BRINGING SUBSIDENT DRY AIR
ALOFT...SUPPRESSING ANY SIGNIFICANT CONVECTION ACROSS THE
REGION. AT SURFACE...MARINE OBSERVATIONS SHOW EASTERLY WINDS
15 TO 20 KT OVER THE EAST AND CENTRAL BASIN. WINDS OVER THE
NORTHWEST BASIN...NORTH OF 17N WEST OF 79W...ARE SHIFTING
SOUTH-SOUTHEAST 10 TO 15 KT...DUE TO A COLD FRONT CURRENTLY
OVER THE EASTERN GULF OF MEXICO. THIS FRONT IS EXPECTED TO ENTER
THE NORTHWEST CARIBBEAN BASIN OVER THE NEXT  24 HOURS.

WEST AND CENTRAL ATLANTIC OCEAN...
UPPER LEVEL RIDGE IS OVER MOST OF THE CENTRAL ATLANTIC
BASIN...SUPPORTING A SURFACE 1022 MB HIGH NEAR 28N56W. THIS
FEATURE IS BRINGING MOSTLY FAIR WEATHER TO THE CENTRAL REGION
NORTH OF 20N WEST OF 45W. TIGHTENING SURFACE PRESSURE GRADIENT
OVER THE WESTERN ATLANTIC WILL CREATE GALE FORCE WINDS NORTH OF
29N WEST OF 75W...AS A LOW PRESSURE SYSTEM ENTERS THIS REGION
OVER THE NEXT 24 HOURS...BRINGING A COLD FRONT ALONG WITH IT.
SOME OF THE SHOWERS ASSOCIATED WITH THIS COMING LOW HAS ALREADY
ENTERED THE WESTERN ATLANTIC...MOSTLY NORTH OF THE DISCUSSION
AREA.

EAST ATLANTIC OCEAN...
A 992 MB OCCLUDED LOW PRESSURE SYSTEM IS OVER THE EASTERN
ATLANTIC BASIN...SPINNING NEAR 31N31W. COMPUTER MODELS INDICATE
THIS SYSTEM WILL SLOWLY MOVE SOUTHEAST TO NEAR 28N27W OVER THE
NEXT 24 HOURS. WATER VAPOR IMAGERY SHOWS THIS SYSTEM HAS LOST
UPPER LEVEL SUPPORT. ONLY AN UPPER LEVEL CLOSED LOW IS SPINNING
OVER THE SURFACE LOW. NEVERTHELESS...THIS SYSTEM CONTINUES TO
PRODUCE MULTIPLE SURGES OF CLOUD BOUNDARIES RESULTING IN SEVERAL
LAYERS OF FRONTS AROUND THE CENTER. THE FIRST ONE ANALYZED
EXTENDS AROUND THE LOW ALONG THE NORTHEAST SEMI-CIRCLE AS AN
OCCLUDED FRONT AND BECOMES A WEAK COLD FRONT ALONG 31N22W 28N22W
25N23W. A SECOND COLD FRONT HAS DETACHED FROM THE LOW CENTER BUT
CONTINUES TO MAINTAIN COLD CHARACTERISTICS. THIS FRONT IS
ANALYZED ALONG 32N26W 29N25W 26N28W. A THIRD COLD FRONT EXTENDS
AROUND THE LOW ALONG THE EASTERN SEMI-CIRCLE AS AN OCCLUDED
FRONT AND CONTINUES AS A COLD FRONT ALONG 31N28W 29N29W 28N30W.
THE CONVECTION WITHIN THESE THREE FRONT COVER AN AREA FROM 24N
TO BEYOND 32N BETWEEN 18W AND 29W. GALE FORCE WINDS ARE IN
EFFECT NORTH OF 26N BETWEEN 38W AND 44W...EXPECTED TO CONTINUE
OVER THE NEXT 24 HOURS.

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

$$

GARCIA




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