AXNT20 KNHC 110538
TWDAT
TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0345 UTC.
...ITCZ...
ITCZ AXIS IS CENTERED ALONG 5N8W 4N21W 1N32W ACROSS THE EQUATOR
NEAR 38W TO INLAND OVER SOUTH AMERICA NEAR 2S46W. SCATTERED
MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM S OF ITCZ
BETWEEN 16W-19W.
...DISCUSSION...
GULF OF MEXICO...
LOW PRESSURE MAINTAINS CONTROL OVER THE ENTIRE GULF WATERS WITH
A FRONTAL SYSTEM REMAINING INLAND OVER SOUTHERN PLAIN STATES. A
SHORTWAVE UPPER TROUGH CENTERED FROM AN UPPER LOW OVER E KANSAS
EXTENDS S OVER TEXAS MOVING TOWARD LOWER MISSISSIPPI VALLEY. AN
UPPER RIDGE COVERS THE GULF ANCHORED IN THE E PACIFIC AND
CONTINUES TO DRAW TROPICAL MOISTURE ACROSS MEXICO AND THE GULF
WATERS. SOUTHERLY SURFACE WINDS ACCOMPANIED BY LOW-LEVEL
MOISTURE AND INSTABILITY ARE COMBINING TO GENERATE SCATTERED
SHOWERS/ISOLATED THUNDERSTORMS INLAND OVER S MISSISSIPPI AND
ALABAMA WELL AS IN THE NE GULF WATERS N OF 27N E OF 90W ACROSS
THE FLORIDA PENINSULA. A SQUALL LINE ASSOCIATED WITH THE NEXT
FRONT TO ENTER THE GULF IS OVER NW LOUISIANA AND THROUGH
ARKANSAS.
CARIBBEAN SEA...
THE REMNANTS OF A STATIONARY FRONT CROSSES CENTRAL ATLC TO OVER
THE LEEWARD ISLANDS JUST N OF GUADELOUPE WITH A SHEAR AXIS
CONTINUING W TO 16N71W. ISOLATED SHOWERS ARE N OF THE SHEAR
AXIS TO OVER THE GREATER ANTILLES. SCATTERED/BROKEN LOW CLOUDS
WITH POSSIBLE ISOLATED SHOWERS DOT THE AREA WITHIN 120 NM OF
LINE FROM COLOMBIA NEAR 11N74W TO OVER W CUBA NEAR 23N83W. THE
REMAINDER OF THE CARIBBEAN IS EXPERIENCING FAIR WEATHER TONIGHT.
ATLANTIC OCEAN...
SURFACE RIDGE OVER THE W ATLC IS ANCHORED BY A 1022 MB HIGH JUST
W OF BERMUDA NEAR 32N66W. ISOLATED SHOWERS USHERED IN ON THE
WEAK UPPER FLOW EXTEND BETWEEN THE BAHAMA ISLANDS AND CUBA W OF
75W. A DEEP LAYER TROUGH REMAINS OVER THE REMAINDER OF THE W AND
OVER CENTRAL ATLC N OF 20N FROM 35W-70W SUPPORTING A COMPLEX
FRONTAL BOUNDARY THAT EXTENDS FROM A 1007 MB LOW N OF THE
MADEIRA ISLANDS THROUGH 32N15N ALONG 27N28W 29N37W TO A 1010 MB
LOW NEAR 28N42W ALONG 21N48W TO THE LEEWARD ISLANDS JUST N OF
GUADELOUPE. SCATTERED SHOWERS AND POSSIBLE ISOLATED
THUNDERSTORMS ARE WITHIN 250 NM NW OF THE FRONT BETWEEN
36W-58W. AN ILL-DEFINED UPPER LEVEL RIDGE EXETNDS FROM TROPICS
NEAR 6N41W TO NEAR THE CANARY ISLANDS KEEPING CONDITIONS FAIR
ACROSS THE REMAINDER OF THE E ATLC.
FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE


forecast by WALLACE
updated at 105 AM EST THU MAR 11 2010

AXPZ20 KNHC 110244
TWDEP
TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU MAR 11 2010
TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM
THE EQUATOR TO 32N...EAST OF 140W.
BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0115 UTC.
...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE WAS ANALYZED ALONG A LINE
FROM 05N77W TO 07N90W TO 05N104W TO 07N120W TO 04N140W.
SCATTERED MODERATE TO STRONG CONVECTION LIED WITHIN 90 NM N OF
THE ITCZ AXIS E OF 78W ALONG THE COLOMBIAN COAST AS WELL AS
WITHIN 150 NM S OF THE ITCZ AXIS BETWEEN 87W AND 96W. A TROUGH
IS EMBEDDED IN THE ITCZ FROM 10N120W TO 03N123W. SCATTERED
MODERATE CONVECTION WAS FOUND WITHIN 210 NM W OF THE TROUGH FROM
05N TO 08N AND WITHIN 300 NM E OF THE TROUGH FROM 05N TO 10N.
...DISCUSSION...
AN UPPER LEVEL TROUGH AXIS EXTENDS FROM W TEXAS THROUGH NW
MEXICO TO 20N140W. A STRONG UPPER JET LIES TO THE S OF THIS
TROUGH AXIS WITH A CORE OF WESTERLY WINDS IN EXCESS OF 150 KT E
OF 120W. SOUTHWESTERLY UPPER LEVEL WINDS CONTINUE TO ADVECT
TROPICAL MOISTURE NORTHEASTWARD ALOFT WHICH IS MANIFESTED IN THE
FORM OF A BROKEN BAND OF CIRRUS CLOUDS BETWEEN 150 NM AND 550 NM
S OF THE TROUGH AXIS. MODERATE TO STRONG SUBSIDENCE AND DRY
STABLE AIR IS NOTED ON WATER VAPOR IMAGERY NORTH OF THE TROUGH
AXIS. A SCATTERED TO BROKEN STRATOCUMULUS DECK CAN BE SEEN IN
INFRARED IMAGERY IN THIS REGION. THIS TROUGH WILL SHIFT E OVER
THE NEXT FEW DAYS...MAKING WAY FOR RIDGING BEHIND IT THROUGH THU
NIGHT. BY FRI...A DEEP LAYERED TROUGH WILL MOVE INTO NW WATERS.
THE COLD FRONT ASSOCIATED WITH THIS NEW TROUGH IS EXPECTED TO BE
WEAK.
A BROAD UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED NEAR
08N116W INFLUENCES THE REMAINDER OF THE DISCUSSION AREA. A RIDGE
AXIS EXTENDS FROM THE ANTICYCLONE NE INTO THE GULF OF FONSECA
WHILE A SECOND RIDGE AXIS EXTENDS W OF THE ANTICYCLONE TO
08N140W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS
OBSERVED NEAR THE SURFACE TROUGH EMBEDDED IN THE ITCZ NEAR 120W
UNDER THE MODERATE UPPER LEVEL DIFFLUENCE ASSOCIATED WITH THIS
WESTERN RIDGE AXIS ALOFT. PLEASE SEE THE SECTION ABOVE FOR
DETAILS. FARTHER E...SCATTERED MODERATE TO STRONG CONVECTION
ALONG THE ITCZ BETWEEN 87W AND 96W LIES IN A POOL OF 2.25 TO
2.50 INCH PRECIPITABLE WATER VALUES BUT ALSO UNDER A REGION OF
INCREASING UPPER LEVEL CONFLUENCE. THEREFORE...THE CONVECTION
HERE IS EXPECTED TO DISSIPATE OVER THE NEXT 24 HOURS.
AT THE SURFACE...1029 MB HIGH PRES LIES OVER FAR NW WATERS NEAR
29N140W WHILE CONTINUED TROUGHING LIES OVER THE SW U.S. WITH A
DISSIPATING STATIONARY FRONT FOUND OFF THE NORTHERN BAJA AND
CALIFORNIA COAST FROM 31N117W TO 33N126W. THE STRONG PRES
GRADIENT BETWEEN THIS TROUGHING AND THE SURFACE RIDGE
AXIS...WHICH EXTENDS SOUTHEAST FROM THE HIGH TO NEAR
15N105W...IS GENERATING 20 TO 25 NW WINDS OFF THE NORTHERN BAJA
CALIFORNIA COAST. THE ASCAT PASS FROM 1652 UTC CONFIRMED THESE
WINDS ARE IN PLACE OFF THE W COAST OF BAJA CALIFORNIA. THE BROAD
UPPER LEVEL TROUGHING OVER THE SW U.S. WILL MOVE E OVER THE NEXT
TWO DAYS AND WINDS WILL BEGIN TO DIMINISH AND SHRINK SOUTHWARD.
SIGNIFICANT WAVE HEIGHTS PEAKED AT 16 FT IN THE NW SWELL OFF THE
NORTHERN BAJA CALIFORNIA COAST AND WILL GRADUALLY SUBSIDE AS THE
SWELL PROPAGATES SOUTHWARD. LOW PRES AT THE SURFACE ASSOCIATED
WITH THE LEADING EDGE OF THE BROAD TROUGH ALOFT HAS SHIFTED
SOUTHEASTWARD INTO EASTERN MEXICO WITH 996 MB LOW PRES ANALYZED
NEAR 22N98W. THE PRES GRADIENT ALONG THE MEXICAN PACIFIC COAST
NEAR 20N HAS STRENGTHENED BETWEEN THIS LOW PRES TO THE E AND THE
RIDGE TO THE W. NW TO N WINDS ARE EXPECTED TO HOVER NEAR 20 KT
THERE AND INTO THE SOUTHERN GULF OF CALIFORNIA FOR THE NEXT TWO
DAYS.
SOUTH OF THE SURFACE RIDGE AXIS LIES A BROAD AREA OF STRONG NE
TRADE WINDS. THE 1652 AND 1834 UTC ASCAT PASSES SHOWED 20 TO 25
KT WINDS W OF 115W FROM 05N TO 24N WITH SOME RETRIEVALS AS HIGH
AS 30 KT. TONIGHT...THE HIGH PRES OVER NW WATERS IS FORECAST TO
MOVE SE AHEAD OF THE APPROACHING COLD FRONT...SHIFTING THE RIDGE
AXIS FARTHER SOUTH. THIS WILL COMPRESS THE TRADES SOUTHWARD
TOMORROW AND THE AREA OF 20 TO 25 KT WINDS WILL SHRINK WESTWARD
FRI AS THE HIGH PRES TO THE N WEAKENS.
GAP WINDS...
20 KT N WINDS ARE EXPECTED TO FUNNEL FROM THE GULF OF MEXICO
SOUTHWARD INTO THE GULF OF TEHUANTEPEC BY THE END OF THE
FORECAST PERIOD ON FRI EVENING.
FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE


forecast by SCHAUER