[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 101729
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT SAT MAY 10 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.

...TROPICAL WAVES...

TROPICAL WAVE IS ALONG 42W/43W S OF 10N MOVING W 15 KT. VISIBLE
IMAGERY REVEALS A FAIR AMOUNT OF LOW-LEVEL CYCLONIC TURNING
...HOWEVER BASED ON A RECENT QSCAT PASS IT IS ABOVE THE SFC. THE
MIMIC TPW ANIMATION SHOWS GOOD CONTINUITY OF THIS WAVE WITH ITS
OVERALL MOISTURE FIELD THINNING SLIGHTLY AND BECOMING MORE
ABSORBED IN THE ITCZ.  SCATTERED SHOWERS AND TSTMS ARE WITHIN
180 NM E OF THE AXIS FROM 3N-6N.

...THE ITCZ...

ITCZ AXIS IS CENTERED ALONG 7N12W 5N23W 2N34W 3N41W 0N50W.
SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 150 NM N AND
180 NM S OF THE AXIS BETWEEN 22W-33W...WITHIN 120 NM N OF THE
AXIS BETWEEN 32W-40W...AND WITHIN 120 NM N OF THE AXIS W OF 45W.

...DISCUSSION...

THE GULF OF MEXICO...

A SPRAWLING MID TO UPPER HIGH IS SITUATED OVER THE BAY OF
CAMPECHE PROVIDING ANTICYCLONIC FLOW ALOFT GULF-WIDE. A
SUBTROPICAL JET OVER THE EPAC IS ADVECTING HIGH LEVEL CLOUDS
ACROSS THE N HALF OF THE GULF...BUT THIS FAINT MOISTURE PLUME
DRIES OUT QUICKLY ON THE DOWNWARD BRANCH OF THE RIDGE. AT THE
SFC...LIGHT TO MODERATE S TO SW FLOW DOMINATES MUCH OF THE AREA
ON THE WRN PERIPHERY OF CENTRAL ATLC SFC HIGH PRES. DESPITE THE
MOIST LOW-LEVEL FLOW...SIGNIFICANT CLOUD COVER IS VERY LIMITED
AND MAINLY FAIR...VERY WARM AND HUMID CONDITIONS ARE ON TAP FOR
THE REGION TODAY. HOWEVER...A CHANGE IS ON THE WAY AS AN UPPER
TROUGH OVER THE ROCKIES SHIFTS E SUPPORTING A COLD FRONT WHICH
WILL LIKELY ENTER THE NW WATERS TOMORROW MORNING.

THE CARIBBEAN SEA...
ELONGATED MID TO UPPER TROUGHING STRETCHES FROM PUERTO RICO TO S
NICARAGUA WITH A RIDGE BUILDING TO ITS W. A 50-70 KT UPPER JET
LIES ON THE E SIDE OF THE TROUGH PRODUCING A PLUME OF MAINLY
HIGH LEVEL CLOUDS WITHIN 300 NM E OF THE TROUGH AXIS. THE
DENSEST CLOUD COVER IS OVER THE NRN LEEWARD ISLANDS CLOSER TO
THE JET CORE. MORE SIGNIFICANT DEEP CLOUDINESS AND EMBEDDED
SCATTERED TSTMS IS OVER THE EXTREME SW CARIB S OF 11N W OF 79W
TRIGGERED BY LOW-LEVEL CONVERGENCE. OTHERWISE...THE TYPICAL
SCATTERED STREAMS OF LOW-LEVEL CLOUDS...WHICH LIKELY CONTAIN
ISOLATED SHOWERS...ARE BEING STEERED ACROSS THE SEA BY MODERATE
TO STRONG TRADES. THE E TRADES ARE QUITE STRONG...25-30
KT...NEAR THE COLOMBIAN COAST TODAY AND THIS IS EXPECTED TO
CONTINUE THROUGH TOMORROW.

THE ATLANTIC OCEAN...

LARGE SCALE UPPER TROUGHING LIES OVER MUCH OF THE W ATLC. THE
MAIN TROUGH IS OVER THE NE CONUS EXTENDING SW TO NEAR 28N65W.
ANOTHER AXIS EXTENDS FROM 23N60W THRU PUERTO RICO AND A COUPLE
OF OTHER SHORTWAVES ARE MAINTAINING THIS OVERALL BROAD TROUGHING
PATTERN. DIFFLUENCE ALOFT AND INSTABILITY NEAR THE SHORTWAVES IS
PRODUCING A FEW AREAS OF SIGNIFICANT SHOWER/TSTM ACTIVITY. THE
MAIN TWO AREAS...BASED ON IR IMAGERY AND LIGHTNING DATA...IS N
OF 31N BETWEEN 65W-69W AND FROM 26N-31N BETWEEN 59W-66W.
LIGHTNING ACTIVITY HAS BEEN INCREASING IN BOTH OF THESE CLUSTERS
OVER THE PAST COUPLE OF HOURS. A SMALLER WEAKENING PATCH IS FROM
23N-26N BETWEEN 52W-54W. AT THE SFC...A 1021 MB HIGH PRES NEAR
28N51W IS PROVIDING RIDGING ACROSS THE ENTIRE SUBTROPICAL W ATLC.

IN THE E ATLC...AN UPPER TROUGH IS SWEEPING E ACROSS THE N
WATERS ALONG 22W PROVIDING SOME SUPPORT FOR A FRONTAL BOUNDARY
ALONG 32N32W TO A WEAK 1018 MB LOW NEAR 27N37W THEN DISSIPATING
TO 23N51W. ONLY A NARROW BAND OF LOW CLOUDS AND ISOLATED SHOWERS
ARE EVIDENT WITHIN 90 NM E OF THE LOW/FRONT N OF 26N. MID TO
UPPER RIDGING LIES ABOVE THE TROPICS WITH A MEAN AXIS ALONG 8N.
UPPER DIFFLUENCE ON THE S SIDE OF THE RIDGE IS ENHANCING
CONVECTION IN THE ITCZ W OF 25W. ELSEWHERE...ZONAL FLOW ALOFT IS
KEEPING CONDITIONS RATHER TRANQUIL. AT THE SFC...A 1024 MB HIGH
SE OF THE AZORES NEAR 35N20W IS PROVIDING LIGHT WINDS IN THE
SUBTROPICS AND MAINLY 15-20 KT NE/E WINDS ACROSS THE TROPICS.

$$
CANGIALOSI


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