[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 271108
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT TUE OCT 27 2009

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1045 UTC.

...TROPICAL WAVES...

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 23W/24W ON TOP OF THE
CAPE VERDE ISLANDS. THE MOVEMENT IS NOT EASY TO JUDGE RIGHT NOW.
STRONG SHOWERS IN ONE CELL FROM 14N TO 15N BETWEEN 23W AND 25W.
OTHER WEAKER SHOWERS ARE POSSIBLE FROM 10N TO 17N BETWEEN
20W AND 28W.

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 41W/42W TO THE SOUTH
OF 16N. THE MOVEMENT IS NOT EASY TO JUDGE RIGHT NOW. THIS WAVE
JUST HAS BEEN INCLUDED IN THE ANALYSIS FOR THIS MAP. IT IS
POSSIBLE TO TRACK ITS MOVEMENT IN SATELLITE IMAGERY FROM THE
LAST FEW DAYS. DISORGANIZED ISOLATED SHOWERS ARE FROM 5N TO 11N
BETWEEN 40W AND 46W. SOME OF THIS PRECIPITATION IS ALSO PART
OF THE ITCZ PRECIPITATION.

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 57W/58W TO THE SOUTH
OF 17N MOVING WESTWARD 10 TO 15 KT. AN UPPER LEVEL CYCLONIC
CIRCULATION CENTER HAS BEEN MOVING ACROSS THE VIRGIN ISLANDS TO
PUERTO RICO DURING THE LAST SIX HOURS. CYCLONIC FLOW AROUND THIS
CENTER COVERS THE CARIBBEAN SEA AND THE ATLANTIC OCEAN FROM 10N
TO 25N BETWEEN 53W AND HAITI. ISOLATED MODERATE SHOWERS AND
POSSIBLE THUNDERSTORMS COVER THE AREA FROM 11N TO 16N BETWEEN
52W AND 61W. OTHER ISOLATED MODERATE SHOWERS ARE IN THE
CARIBBEAN SEA FROM 16N TO 18N BETWEEN 62W AND 71W.

...ITCZ...

ALONG 7N/8N BETWEEN AFRICA AND 40W...AND FROM 9N TO 10N BETWEEN
40W AND 60W. ISOLATED STRONG SHOWERS AND THUNDERSTORMS FROM
8N TO 13N BETWEEN AFRICA AND 20W. ISOLATED MODERATE SHOWERS
FROM 7N TO 11N BETWEEN 20W AND 40W...AND FROM 7N TO 12N BETWEEN
50W AND 60W.

...DISCUSSION...

THE GULF OF MEXICO...
A DEEP LAYER TROUGH THAT IS MOVING THROUGH CENTRAL TEXAS AND
NORTHERN MEXICO SUPPORTS THE CURRENT COLD FRONT THAT PASSES
THROUGH SOUTHWESTERN LOUISIANA TO THE MEXICO GULF COAST NEAR
21N98W. A LARGE-SCALE UPPER LEVEL RIDGE IS IN THE CENTRAL GULF
OF MEXICO. MOSTLY UPPER LEVEL SOUTHWESTERLY WINDS ALSO COVER THE
AREA TO THE EAST OF THE APPROACHING TEXAS TROUGH. A STATIONARY
FRONT HAS DEVELOPED IN THE NORTHEASTERN GULF OF MEXICO.
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED FROM THE SOUTHWESTERN
CORNER OF THE AREA...TO THE NORTHEASTERN CORNER...TO THE
SOUTHEASTERN CORNER.

THE CARIBBEAN SEA...
AN UPPER LEVEL CYCLONIC CIRCULATION CENTER HAS BEEN MOVING
ACROSS THE VIRGIN ISLANDS TO PUERTO RICO DURING THE LAST SIX
HOURS. CYCLONIC FLOW AROUND THIS CENTER COVERS THE CARIBBEAN SEA
AND THE ATLANTIC OCEAN FROM 10N TO 25N BETWEEN 53W AND HAITI.
ISOLATED MODERATE SHOWERS AND POSSIBLE THUNDERSTORMS COVER THE
AREA FROM 11N TO 16N BETWEEN 52W AND 61W. OTHER ISOLATED
MODERATE SHOWERS ARE IN THE CARIBBEAN SEA FROM 16N TO 18N
BETWEEN 62W AND 71W. LARGE-SCALE UPPER LEVEL CYCLONIC FLOW
COVERS THE AREA TO THE NORTHEAST OF THE LINE FROM 18N80W TO
THE COLOMBIA COAST NEAR 11N75W...AND TO THE EAST OF 70W. THIS
CYCLONIC FLOW IS RELATED TO THE CYCLONIC CIRCULATION CENTER THAT
HAS BEEN MOVING ACROSS THE VIRGIN ISLANDS TO PUERTO RICO DURING
THE LAST SIX HOURS. A SEPARATE AREA OF WEAK UPPER LEVEL CYCLONIC
FLOW COVERS THE AREA FROM 10N TO 20N BETWEEN 80W AND 86W. SHOWERS
AND THUNDERSTORMS FROM 18N TO CUBA BETWEEN 82W AND 83W...AND
ALONG THE PANAMA COAST TO THE SOUTH OF 10N BETWEEN 80W AND 82W.
OTHER ISOLATED MODERATE SHOWERS ARE ALONG THE NICARAGUA COAST.

THE ATLANTIC OCEAN...
LARGE-SCALE UPPER LEVEL ANTICYCLONIC FLOW COVERS THE AREA TO THE
NORTH OF 20N TO THE WEST OF 35W. THIS ANTICYCLONIC FLOW IS ON
TOP OF THE CYCLONIC FLOW THAT IS NEAR PUERTO RICO AND THE VIRGIN
ISLANDS...THAT ALSO COVERS PARTS OF THE ATLANTIC OCEAN. ONE AREA
OF A 700 MB-TO-500 MB VORTICITY MAXIMUM COVERS THE AREA ALONG
68W/69W NEAR 27N. CLOUDS ARE FROM 25N TO 29N BETWEEN 66W AND
71W. A SECOND AREA OF 700 MB-TO-500 MB VORTICITY MAXIMUM IS NEAR
27N54W. THIS FEATURE IS SPREADING CLOUDS FROM 25N TO 29N BETWEEN
50W AND 59W. AN EASTERN ATLANTIC OCEAN DEEP LAYER TROUGH EXTENDS
FROM A CYCLONIC CIRCULATION CENTER THAT IS NEAR 31N25W TO
21N29W. A SHEAR AXIS CONTINUES FROM 21N29W TO 21N42W AND 22N53W.
THIS AXIS EVENTUALLY FEEDS INTO THE COMPARATIVELY LARGER AREA OF
CYCLONIC FLOW THAT IS MOVING AROUND THE VIRGIN ISLANDS TO PUERTO
RICO DURING THE LAST SIX HOURS. A DISSIPATING COLD FRONT GOES
FROM 34N19W TO 25N26W.

$$
MT



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