Prognostic Meteorological Discussion
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FXCA20 KWBC 151829
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
228 PM EDT MON SEP 15 2014

AT 15 UTC HURRICANE EDOUARD CENTERED NEAR 27.3N 55.5W...WITH
MAXIMUM SUSTAINED WINDS OF 90KT AND CENTRAL PRESSURE OF 966 HPA.
THE HURRICANE IS MOVING TO THE NW AT 12KT.

AT 15 UTC HURRICANE ODILE CENTERED NEAR 24.7N 111.3W...WITH
MAXIMUM SUSTAINED WINDS OF 85KT AND CENTRAL PRESSURE OF 955 HPA.
THE HURRICANE IS MOVING TO THE NORTHWEST AT 12KT.

DISCUSSION FROM SEPTEMBER 15/00UTC: PERSISTENT MID/UPPER LEVEL
RIDGE OVER THE CENTRAL-NORTHERN STATES OF MEXICO IS PROVIDING THE
VENTILATION AND STEERING FLOW TO HURRICANE ODILE. THE HURRICANE IS
FORECAST TO WEAKEN TO A TROPICAL STORM EARLY ON TUESDAY AND
DOWNGRADE TO A DEPRESSION EARLY ON WEDNESDAY. STRONG TOPOGRAPHICAL
FORCING ACROSS THE BAJA PENINSULA WILL LEAD TO HEAVY RAINFALL
AMOUNTS...WITH ACCUMULATION OF 75-125MM/DAY AND MAXIMA OF
250-300MM THROUGH TUESDAY MORNING. THROUGH WEDNESDAY THIS WILL
DECREASE TO 25-50MM/DAY AND MAXIMA OF 75-100MM.
FURTHERMORE...FEEDER BAND CONVECTION IS TO AFFECT WESTERN PORTIONS
OF MEXICO...WITH ACTIVITY ALONG THE SIERRA MADRE BETWEEN WESTERN
CHIHUAHUA-SONORA AND SINALOA-NAYARIT TO RESULT IN RAINFALL AMOUNTS
OF 15-30MM/DAY AND MAXIMA OF 40-80MM.

A TUTT TO THE SOUTH OF THIS RIDGE EXTENDS OVER THE SOUTHERN
GULF-SOUTHERN STATES OF MEXICO. RIDGE TO THE WEST AND NORTH IS TO
STEER THIS VORTEX SOUTH ACROSS THE SOUTHERN STATES OF
MEXICO...WEAKENING AS IT MEANDER OVER CENTRAL MEXICO LATER ON
TUESDAY. THIS TROUGH IS TO INTERACT WITH THE EASTERN PACIFIC ITCZ
AS IT MEANDERS NORTH OF ITS CLIMATOLOGICAL POSITION. THIS IS TO
ENHANCE CONVECTIVE DEVELOPMENT OVER EL SALVADOR-HONDURAS-GUATEMALA
TO SOUTHERN MEXICO...TO RESULT IN RAINFALL AMOUNTS OF 25-50MM/DAY
AND MAXIMA OF 75-100MM. BUT AS THE TUTT MOVES AWAY TO CENTRAL
MEXICO THIS DECREASES TO 10-15MM/DAY AND MAXIMA OF 20-40MM EARLY
ON WEDNESDAY. AS THE TUTT MOVES TO CENTRAL MEXICO ON TUESDAY IT IS
TO FAVOR RAINFALL AMOUNTS OF 25-50MM/DAY AND MAXIMA OF 75-125MM.
FARTHER SOUTH...ITCZ CONVERGENCE ACROSS WESTERN NICARAGUA/COSTA
RICA TO PANAMA IS TO RESULT IN RAINFALL AMOUNTS OF 10-15MM/DAY AND
MAXIMA OF 20-40MM. THROUGH TUESDAY AFTERNOON-WEDNESDAY MORNING
THIS IS TO DECREASE/INCREASE TO 15-20MM/DAY AND MAXIMA OF 25-50MM.

A TUTT LOW TO THE NORTH OF THE TURKS AND CAICOS ANCHORS A BROAD
TROUGH ACROSS THE GREATER ANTILLES TO THE NORTHERN CARIBBEAN. BEST
DYNAMICAL FORCING WITH THIS FEATURE REMAINS AROUND THE CLOSED
CIRCULATION TO THE NORTH...WITH SOME ENHANCEMENT OVER THE GREATER
ANTILLES AS IT INTERACTS WITH SEA BREEZE RELATED CONVERGENCE. AT
MID LEVELS...A RIDGE EXTENDS TO THE WEST-SOUTHWEST ACROSS THE
NORTHEAST CARIBBEAN ISLANDS...FAVORING A WEAK MID LEVEL CAP
INVERSION. THIS IS NOT STRONG ENOUGH TO COMPLETELY SUPPRESS
CONVECTIVE DEVELOPMENT...BUT IT IS STRONG ENOUGH TO DELAY ONSET OF
DEEP CONVECTION. HURRICANE EDOUARD LIES FAR TO THE
NORTHEAST...WITH NHC FORECASTING THIS CYCLONE TO CONTINUE TRACKING
AWAY FROM THE FORECAST AREA. BROAD UPPER TROUGH PATTERN IS TO
GENERALLY HOLD THROUGH TUESDAY EVENING/EARLY WEDNESDAY MORNING. IT
IS TO THEN RAPIDLY SHEAR TO THE NORTH-NORTHEAST AS A HIGH
AMPLITUDE POLAR TROUGH DEEPENS TO THE WEST ACROSS THE EASTERN USA.
ALTHOUGH BEST ENHANCEMENT IS EXPECTED TO THE NORTH...SOME
CONVECTIVE ENHANCEMENT IS CONVERGENCE/DIURNAL HEATING OVER CENTRAL
HISPANIOLA AND THE CORDILLERA CENTRAL IN PUERTO RICO. IN THIS AREA
EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM.
SIMILAR AMOUNTS ARE EXPECTED ACROSS CUBA-THE BAHAMAS...WHILE OVER
JAMAICA MAXIMA IS TO PEAK AT 15-25MM.

THE SUBEQUATORIAL RIDGE TO THE SOUTH EXTENDS EAST-TO-WEST ACROSS
NORTHERN SOUTH AMERICA...WHILE ANCHORING ON A CLOSED HIGH NEAR THE
ORINOCO DELTA REGION. THROUGH WEDNESDAY MORNING THE HIGH WILL
RELOCATE TOWARDS LA GUAJIRA PENINSULA IN NORTHWEST VENEZUELA...BUT
RIDGE PATTERN IS TO HOLD OVER THE SOUTHERN CARIBBEAN/NORTHERN
SOUTH AMERICA. THE GUIANAS WILL FALL ON THE CONVERGENT SIDE OF
THIS RIDGE...WHICH WILL LIMIT CONVECTIVE DEVELOPMENT TO COASTAL
AREAS...WHERE WE EXPECT ACCUMULATION OF 00-05MM/DAY AND MAXIMA OF
10MM. ACROSS CENTRAL VENEZUELA EXPECTING ACCUMULATION OF
05-10MM/DAY AND MAXIMA OF 15-20MM.

TROPICAL/EASTERLY WAVES INITIALIZED AT 12UTC
INITIAL  24     36     48     60     72     84     96     TYPE
25W     28W    30W    33W    36W    39W    42W    45W     TW
46W     49W    52W    55W    58W    60W    63W    66W     TW
94W     95W    96W    97W    98W    DISP                  TUTT
INDCD.

TROPICAL WAVE ALONG 25W IS TO CONFINE TO THE ATLANTIC ITCZ OVER
THE NEXT FEW DAYS.

TROPICAL WAVE ALONG 46W REACHES THE LESSER ANTILLES LATER ON
WEDNESDAY... WHERE IT IS TO SUSTAIN RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-30MM. THROUGH MID MORNING ON THURSDAY
IT PULLS ACROSS THE VIRGIN ISLES TO PUERTO RICO...MOVING ACROSS
THE ISLAND DURING MAX HEATING. THIS IS TO THEN FAVOR RAINFALL
AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-45MM. FOLLOWING WAVE
PASSAGE...A LONG FETCH SOUTHEASTERLY FLOW IS TO ESTABLISH...WITH
ITCZ MOISTURE LIFTING ACROSS THE FRENCH ISLES TO PUERTO RICO AND
THE VIRGIN ISLES...TO SUSTAIN A PERIOD OF SCATTERED SHOWERS OVER
THE LEEWARD/FRENCH ISLES AND INTO PUERTO RICO/PORTIONS OF
HISPANIOLA. LOOKS LIKE THIS IS GOING TO COINCIDE WITH IMPROVING
MJO CONDITIONS ACROSS THE CARIBBEAN BASIN...WITH CLIMO MODELS
SHOWING NEUTRAL TO WEAK DIVERGENT CONDITIONS ACROSS THE CARIBBEAN
BASIN DURING THE NEXT 15-20 DAYS. AS A RESULT...TRAILING
CONVECTION OVER THE ISLANDS IS TO SUSTAIN ACCUMULATION OF
10-15MM/DAY AND MAXIMA OF 20-35MM.

TUTT OVER THE SOUTHERN GULF SUSTAINS AN INDUCED PERTURBATION IN
THE LOW LEVEL EASTERLIES. THIS TENDS TO WEAKEN AS IT MOVES ACROSS
CENTRAL MEXICO. MEANWHILE...EXPECTING SCATTERED CONVECTION TO
DEVELOP AS THIS INTERACTS WITH THE EASTERN PACIFIC ITCZ...TO
RESULT IN RAINFALL AMOUNTS OF 25-50MM/DAY AND MAXIMA OF 75-100MM.

VALVERDE...IMN (COSTA RICA)
MEDINA...ONAMET (REPUBLICA DOMINICANA)
DAVISON...WPC (USA)
$$




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