[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 151754
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST TUE JAN 15 2008

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN
SECTIONS OF SOUTH AMERICA...AND THE 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
1715 UTC

...THE ITCZ...
THE ITCZ AXIS IS CENTERED ALONG 7N12W 3N20W ALONG THE EQUATOR
BETWEEN 30W AND 44W INTO NE BRAZIL. CLUSTERS OF SCATTERED
MODERATE CONVECTION ARE FROM 2S-4N BETWEEN 44W-50W. SCATTERED
SHOWERS AND ISOLATED TSTMS ARE WITHIN 100 NM N OF AXIS BETWEEN
23W-29W.

...DISCUSSION...

GULF OF MEXICO...
ATTENTION REMAINS FOCUSED IN A DEVELOPING 1012 MB SURFACE LOW
LOCATED OVER THE SW PORTION OF THE GULF NEAR 21N96W. THIS LOW IS
FORECAST TO STRENGTHEN TO A GALE IN ABOUT 24 HOURS OR SO. THIS
SYSTEM IS ALREADY TAKING SHAPE ON SATELLITE IMAGERY THAT SHOWS
SOME CYCLONIC SIGNATURE WITH MOST OF THE SHOWER/TSTM ACTIVITY TO
THE E AND NE OF THE LOW CENTER. A STRONG CUT-OFF LOW MOVING EWD
OVER NORTHERN MEXICO IS SUPPORTING THE DEVELOPMENT OF THIS GALE
THAT IS FORECAST TO MOVE NE ACROSS THE WESTERN GULF...THEN EWD
OVER THE NORTHERN GULF WATERS REACHING THE FLORIDA PANHANDLE
EARLY THU. A GALE WARNING HAS BEEN ISSUED FOR THE NORTHERN
PORTION OF THE GULF OF MEXICO. A STATIONARY FRONT REMAINS
ATTACHED TO THE LOW AND CROSSES THE N YUCATAN PENINSULA/CHANNEL
AND THE BAY OF CAMPECHE. THE LOW WILL DRAG A NEW COLD FRONT
ACROSS THE GULF WED AND THU WITH THE FRONT STALLING OVER THE SE
WATERS THU NIGHT. A SFC TROUGH WAS ANALYZED OVER THE WRN GULF OF
MEXICO FROM THE SFC LOW TO THE UPPER TEXAS COAST. MULTILAYERED
CLOUDS WITH EMBEDDED SHOWERS COVERS A GOOD PORTION OF THE AREA.
THE REMAINDER OF THE AREA IS UNDER THE INFLUENCE OF A BUILDING
LOW-LEVEL RIDGE WITH SEVERAL CENTERS OVER THE SE U.S. ALONG THE
GULF COAST STATES. THE STRONG PRESSURE GRADIENT BETWEEN THE
BUILDING SFC RIDGE AND LOW PRESSURE OVER THE SW GULF IS
PRODUCING MODERATE TO STRONG ELY WINDS ACROSS THE AREA MAINLY W
OF 90W. OTHERWISE...AT UPPER LEVELS...STRONG SWLY WINDS ARE
ADVECTING UPPER LEVEL MOISTURE/HIGH CLOUDS FROM THE EPAC ACROSS
CENTRAL MEXICO INTO THE GULF AND THE FLORIDA PENINSULA.

CARIBBEAN SEA...
A MID-LEVEL RIDGE NOW CENTERED JUST NE OF HISPANIOLA CONTINUES
TO DOMINATE MOST OF THE BASIN LIMITING THE DEVELOPMENT OF DEEP
CONVECTION. HOWEVER...THERE ARE SOME PATCHES OF LOW-LEVEL CLOUDS
WITH EMBEDDED SHOWERS FORMING OVER THE WESTERN CARIBBEAN
WITHIN A BROAD CYCLONIC FLOW. THESE CLOUDS ARE AFFECTING FROM
WESTERN PANAMA TO HONDURAS. ELSEWHERE...A STATIONARY FRONT LIES
ACROSS WESTERN CUBA AND THE YUCATAN CHANNEL/PENINSULA GENERATING
SOME CLOUDINESS AND A FEW SHOWERS. EARLY TRADE WINDS BLOWING
ACROSS THE REMAINDER OF THE CARIBBEAN ARE MOSTLY MODERATE IN
STRENGTH...EXCEPT LOCALLY STRONGER IN THE TYPICAL ZONE NEAR THE
COAST OF COLOMBIA. EXPECT THE FRONTAL BOUNDARY TO WEAKEN ACROSS
THE CARIBBEAN. THE NEXT COLD  IS FORECAST TO REACH THE YUCATAN
CHANNEL/WESTERN CUBA LATE SAT WITH STRONG NORTHERLY WINDS BEHIND
IT. TO THE EAST...A BROAD UPPER-LEVEL RIDGE DOMINATING NRN SOUTH
AMERICA IS ADVECTING MOISTURE/HIGH CLOUDS INTO THE SE CARIBBEAN.

ATLANTIC OCEAN...
A COLD FRONT PASSES SE OF BERMUDAS ENTERING THE AREA NEAR 31N33W
THEN CONTINUES SW ACROSS THE CENTRAL BAHAMAS NEAR 25N75W. AT
THIS POINT IT BECOMES STATIONARY CROSSING WESTERN CUBA AND THE
EXTREME NW CARIBBEAN. THE FRONTAL BOUNDARY IS WELL DEFINED ON
SATELLITE PICTURES NE OF THE BAHAMAS WITH A 70-100 NM WIDE BAND
OF LOW/MID CLOUDS AND SCATTERED SHOWERS. AHEAD OF THE FRONT...
THERE IS A SFC TROUGH THAT RUNS FROM 28N56W TO 20N60W. ANOTHER
SFC TROUGH WAS ADDED TO THE 12Z SURFACE MAP ALONG 12N37W 9N42W
BASED ON A QUIKSCAT PASS FROM THIS MORNING THAT SHOWED THE WIND
SHIFT ASSOCIATED WITH THE TROUGH. SOME SHOWER/TSTM ACTIVITY IS
ON THE TAIL END OF THE TROUGH AND WITHIN 145 NM SE OF THE
NORTHERN END. UPPER-LEVEL DIFFLUENCE IS ENHANCING SOME SHOWER
ACTIVITY ACROSS THE CENTRAL ATLC MAINLY N OF 19N BETWEEN
48W-51W. OTHERWISE...AN SE-MOVING SFC RIDGE...ANCHORED ON A
1030 MB HIGH CENTER NEAR 33N28W...DOMINATES THE REMAINDER OF THE
ATLANTIC FORECAST AREA. MODERATE TO STRONG TRADES ON THE
SOUTHERN SIDE OF THIS FEATURE ARE AFFECTING THE TROPICAL
ATLANTIC FROM THE NWRN COAST OF AFRICA TO 50W. FINALLY...A JET
STREAM BRANCH...WITH CORE WINDS OF 90 TO 110 KT IS SE OF AN
AMPLIFIED MID TO UPPER TROUGH EXTENDING FROM A CUT-OFF LOW NEAR
23N32W TO 18N41W. A BROAD BAND OF TRANSVERSE HIGH CLOUDS...
CROSSING THE CAPE VERDE ISLANDS...ACCOMPANIES THIS JET.

$$
GR




This weather bulletin was brought to you by:
www.nashvilleweather.net