[Tropical] Tropical Weather Discussion

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AXNT20 KNHC 050623 CCA
TWDAT

TROPICAL WEATHER DISCUSSION...COR
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT SUN AUG 05 2007

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.

CORRECTION IN ORDER TO UPDATE THE SECTIONS FOR
TROPICAL WAVES AND THE ITCZ

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 0545 UTC.

...TROPICAL WAVES...
A HIGH AMPLITUDE ATLANTIC OCEAN TROPICAL WAVE IS ALONG 26W/27W
SOUTH OF 21N MOVING WEST 15 KT. THIS WAVE CONTINUES TO EXHIBIT
A LARGE WELL DEFINED AREA OF CYCLONIC TURNING IN THE LOW AND
MIDDLE LEVEL CLOUDS. THE MOST PRONOUNCED ROTATION...WITHOUT DEEP
CONVECTIVE PRECIPITATION...ALREADY HAS CLEARED THE CAPE VERDE
ISLANDS. ISOLATED MODERATE SHOWERS FROM 10N TO 15N BETWEEN
25W AND 30W.

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 43W SOUTH OF 18N MOVING
WEST 15 KT. THIS WEAK WAVE REMAINS DIFFICULT TO LOCATE AS IT IS
EMBEDDED IN THE FLOW OF THE LARGER WAVES TO THE EAST AND WEST.
STABLE AIR AND BROKEN STRATOCUMULUS CLOUDS SURROUND THIS WAVE.
ANY NEARBY PRECIPITATION IS IN THE ITCZ.

A HIGH AMPLITUDE ATLANTIC OCEAN TROPICAL WAVE IS ALONG 59W
MOVING WEST 15 TO 20 KT. THIS LARGE-SCALE WAVE REMAINS FAIRLY
EASILY SEEN WITH A PRONOUNCED INVERTED-V SHAPE IN THE LOW AND
MIDDLE LEVEL CLOUD FIELD. THE NORTHERN PART OF THIS WAVE IS
PASSING THROUGH AN AREA ALREADY OCCUPIED BY THE 26N67W 20N60W
EAST CARIBBEAN SEA MIDDLE TO UPPER LEVEL TROUGH. ITCZ
PRECIPITATION IS FROM 10N TO 13N BETWEEN 50W AND 60W. THIS
WAVE HAS GAINED MOISTURE AS COMPARED TO YESTERDAY BECAUSE
OF THE TROUGH.

A STRONG CARIBBEAN SEA TROPICAL WAVE IS ALONG 86W/87W FROM THE
YUCATAN CHANNEL SOUTHWARD OVER HONDURAS AND NICARAGUA...MOVING
WEST NEARLY 20 KT. UPPER LEVEL ANTICYCLONIC FLOW IS ON TOP OF
THIS WAVE. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS ARE ALONG
THE PACIFIC COASTS FROM WESTERN NICARAGUA TO EL SALVADOR. OTHER
AREAS OF SHOWERS AND THUNDERSTORMS COVER THE CARIBBEAN SEA
NORTH OF 11N WEST OF 82W...INCLUDING LAND AREAS OF NORTHEASTERN
NICARAGUA...SOUTHERN BELIZE...AND THE NORTHEASTERN YUCATAN
PENINSULA.

THE NORTHERN PART OF A TROPICAL WAVE ALONG 97W REACHES INTO THE
SOUTHWESTERN GULF OF MEXICO...SOUTH OF 21N MOVING WEST 15 TO
20 KT. THIS WAVE REMAINS WEAK WITH THE CURRENT POSITION BASED
MOSTLY ON A MODEST WESTWARD SURGE OF MOISTURE NOTED ON THE
UNIVERSITY OF WISCONSIN-CIMSS TPW PRODUCT. SOME OF THE MOISTURE
APPEARS TO BE ROTATING MORE NORTHWESTWARD AROUND THE RIDGING
IN THE GULF OF MEXICO. ALL THE PRECIPITATION FROM THE 86W/87W
TROPICAL WAVE BETWEEN 82W AND 94W OVERSHADOWS THIS WAVE.

...THE ITCZ...
15N17W 12N25W 9N47W 10N52W 13N57W. WIDELY SCATTERED MODERATE
SHOWERS TO ISOLATED STRONG THUNDERSTORMS WITHIN 150 NM ON EITHER
SIDE OF 10N14W 9N30W 8N40W...AND WITHIN 180 NM SOUTH OF 8N40W
11N50W 14N55W. ISOLATED MODERATE SHOWERS WITHIN 120 NM NORTH
OF THE SAME 8N40W 14N55W LINE.

...DISCUSSION...
THE GULF OF MEXICO...
A MIDDLE TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS IN
INTERIOR MEXICO NOW NEAR 25N104W. THIS CYCLONIC CENTER WAS
OVER SOUTH TEXAS ABOUT 24 HOURS AGO. WIDELY SCATTERED MODERATE
SHOWERS TO ISOLATED STRONG THUNDERSTORMS IN MEXICO FROM 20N
TO 29N BETWEEN 102W AND 108W. THE MIDDLE TO UPPER LEVEL CYCLONIC
CIRCULATION CENTER ORIGINALLY OVER THE YUCATAN PENINSULA
24  HOURS AGO NOW IS IN MEXICO NEAR 19N99W. UPPER LEVEL
ANTICYCLONIC FLOW ON TOP OF THE WESTERN CARIBBEAN SEA TROPICAL
WAVE. MIDDLE TO UPPER LEVEL DRY AIR RUNS FROM THE SOUTHWESTERN
CORNER OF THE AREA TO THE CENTRAL GULF WATERS TO THE EAST WITHIN
100 NM ON EITHER SIDE OF 20N96W 25N92W 27N82W. UPPER LEVEL
MOISTURE WITH THE ANTICYCLONIC FLOW ON TOP OF THE TROPICAL WAVE
IS SOUTH OF 26N BETWEEN 80W AND 95W. A SURFACE RIDGE GOES FROM
A 1020 MB HIGH PRESSURE CENTER NEAR 28N70W IN THE ATLANTIC OCEAN
TO LAKE OKEECHOBEE IN FLORIDA...TO 28N71W TO 27N88W.

THE CARIBBEAN SEA...
A TROPICAL WAVE IS ALONG 86W/87W FROM THE YUCATAN CHANNEL
SOUTHWARD OVER HONDURAS AND NICARAGUA. UPPER LEVEL ANTICYCLONIC
FLOW IS ON TOP OF THIS WAVE. NUMEROUS STRONG SHOWERS AND
THUNDERSTORMS ARE ALONG THE PACIFIC COASTS FROM WESTERN NICARAGUA
TO EL SALVADOR. OTHER AREAS OF SHOWERS AND THUNDERSTORMS COVER
THE CARIBBEAN SEA NORTH OF 11N WEST OF 82W...INCLUDING LAND
AREASNORTHEASTERN NICARAGUA...SOUTHERN BELIZE...AND THE
NORTHEASTERN YUCATAN PENINSULA. MIDDLE TO UPPER LEVEL DRY AIR
IS MOVING ANTICYCLONICALLY INTO THE AREA...TO THE WEST OF THE
ATLANTIC OCEAN-TO-EASTERN CARIBBEAN SEA TROUGH. ISOLATED
MODERATE SHOWERS ARE NORTH OF 17N73W 15N69W 15N60W ALONG THE
TROUGH. AN INCREASE IN MOISTURE IS LIKELY IN THE EASTERN
CARIBBEAN SEA DURING THE NEXT COUPLE OF DAYS AS THE LARGE
TROPICAL WAVE IN THE TROPICAL ATLANTIC OCEAN APPROACHES.

THE ATLANTIC OCEAN...
AN UPPER LEVEL RIDGE EXTENDS FROM THE NORTHWESTERN CARIBBEAN
SEA NEAR 19N86W...THROUGH THE STRAITS OF FLORIDA AND BEYOND
32N65W NEAR BERMUDA. A MIDDLE TO UPPER LEVEL TROUGH EXTENDS
FROM A CYCLONIC CIRCULATION CENTER NEAR 26N57W TO 20N60W
TO THE EAST CENTRAL CARIBBEAN SEA. ISOLATED MODERATE SHOWERS
ARE WITHIN 90 TO 150 NM ON EITHER SIDE OF 18N62W 21N58W 27N55W.
A CENTRAL ATLANTIC OCEAN MIDDLE TO UPPER LEVEL TROUGH EXTENDS
FROM A SLOWLY-DEVELOPING CYCLONIC CIRCULATION CENTER NEAR 30N32W
TO 20N40W TO 15N44W. A MIDDLE TO UPPER LEVEL TROUGH PASSES
THROUGH 32N12W TO THE CANARY ISLANDS AND 28N15W. AN ATLANTIC
OCEAN 1027 MB HIGH PRESSURE CENTER IS NEAR 35N36W. BROAD SURFACE
ANTICYCLONIC FLOW IS NORTH OF 21N BETWEEN AFRICA AND THE 59W
TROPICAL WAVE.

$$
MT





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