Home


000
AXPZ20 KNHC 121603
TWDEP

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU FEB 12 2015

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC.


...SPECIAL FEATURES...

GULF OF TEHUANTEPEC GALE WARNING...NORTHERLY WINDS OF 30-45 KT WITH SEAS UP TO 15-17 FT...ARE EXPECTED TO PERSIST THROUGH SUN MORNING. THE AERIAL EXTENT OF THE STRONGEST WINDS WILL SLIGHTLY INCREASE ON SAT AS HIGH PRES ACROSS THE WESTERN GULF OF MEXICO WILL BE REINFORCING BY A STRONGER HIGH PRES BUILDING S ACROSS THE CENTRAL PLAINS OF UNITED STATES. THE NORTHERLY WINDS WILL GRADUALLY DIMINISH TO 20 KT OR LESS LATE MON MORNING. ANOTHER GALE EVENT IS THEN POSSIBLE LATE MON NIGHT THROUGH EARLY NEXT WEEK. THE RESULTANT SWELL CONTINUES TO PROPAGATE SE THROUGH SW...MERGING WITH ENE SWELL GENERATED FROM THE GULF OF PAPAGAYO GALE EVENT...MERGING WITH CROSS-EQUATORIAL SW SWELL AND ALSO MERGING WITH LONG PERIOD NW SWELL. AS A RESULT...EXPECT AN AREA OF COMBINED SEAS IN THE 8-12 FT RANGE S OF 13N-14N BETWEEN 92W- 93W AND 110W OVER THE NEXT 48 HOURS. SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/ WMO HEADERS MIAHSFEP2/FZPN03 KNHC FOR MORE DETAILS.

GULF OF PAPAGAYO GALE WARNING...MINIMAL GALE CONDITIONS ARE EXPECTED PERSIST THROUGH THE MORNING HOURS. THE NARROW BAND OF GALE CONDITIONS ARE SURROUNDED BY A LARGE AREA OF FRESH TO STRONG NE WINDS...INCLUDING IN THE GULF OF FONSECA. SEAS ARE UP TO 13 FT DOWNWIND OF THE GALE AREA. EXPECT THE NE FLOW TO DIMINISH TO 20-25 KT DURING THE AFTERNOON AND EVENING HOURS AND INCREASE AGAIN TO 25-30 KT AT NIGHT INTO THE EARLY MORNING HOURS THROUGH THE FORECAST PERIOD. AS HIGH PRES BUILDS ACROSS THE WESTERN CARIBBEAN ON SAT...EXPECT INCREASING WINDS TO 25-30 KT ACROSS THE GULF OF FONSECA BY SAT NIGHT...THEN ACROSS THE GULF OF PAPAGAYO BY EARLY SUN MORNING. SEE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFEP2/FZPN03 KNHC FOR MORE DETAILS.


...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE ITCZ AXIS EXTENDS FROM 05N90W TO 04N100W TO 05N110W TO 07N120W TO 03N140W. SCATTERED MODERATE CONVECTION IS NOTED FROM 03N TO 06N BETWEEN 90W AND 108W...AND FROM 04N TO 06N BETWEEN 130W AND 135W. SCATTERED MODERATE ISOLATED STRONG CONVECTION CAN BE FOUND FROM 09N TO 11N BETWEEN 115W AND 122W...AND FROM 04N TO 07N BETWEEN 124W AND 130W.


...DISCUSSION...

A STATIONARY FRONT IS OVER THE FAR NW CORNER OF THE AREA AND EXTENDS FROM 30N136W TO 27N140W. SCATTERED MODERATE CONVECTION IS SEEN WITHIN 60 NM AHEAD OF THE FRONT. A 1023 MB HIGH PRES FALLOWS THE FRONT AND IS CENTERED NEAR 30N146W. THE FRONT WILL GRADUALLY DISSIPATE THROUGH THIS EVENING. THE HIGH PRES WILL MOVE NE TO A POSITION NEAR 35N134W AND GRADUALLY STRENGTHEN. THIS WILL INCREASE THE PRES GRADIENT ACROSS THE FORECAST WATERS W OF 120W THIS WEEKEND. AS A RESULT...EXPECT A LARGE AREA OF FRESH TO STRONG TRADES PARTICULARLY N OF THE ITCZ W OF 120W.

MODEL GUIDANCE SUGGESTS THE DEVELOPMENT OF ONE OR TWO TROUGHS N OF THE ITCZ W OF 120W THROUGH SAT NIGHT. WHILE THERE MAYBE AN ISSUE WITH CONVECTIVE FEEDBACK...THE DETERMINISTIC RUNS OF THE GFS...ECMWF...AND UKMET ALL INCREASE WINDS TO GALE FORCE WITH A TROUGH NEAR OR ALONG 126W BY SAT NIGHT...WHILE GEFS 34 KT PROBABILITIES ARE GREATER THAN 20 PERCENT. SREF PACIFIC 34 KT PROBABILITIES ARE 10-15 PERCENT. FOR NOW WILL CAP WINDS ASSOCIATED WITH THIS FEATURE AT 30 KT...ALTHOUGH THIS WILL NEED TO BE MONITORED AS CONDITIONS PROGRESS.

LARGE NW SWELLS...WITH WAVE PERIODS OF 21-22 SECONDS...CONTINUE TO PROPAGATE ACROSS MOST OF THE WATERS W OF 115W WITH SEAS UP TO 17-18 FT NEAR 30N140W. THIS SWELL EVENT WILL CONTINUE TO PROPAGATE TO THE E-SE...REACHING THE COAST OF THE BAJA CALIFORNIA THROUGH THIS EVENING...AND THE REVILLAGIGEDO AND LAS TRES MARIAS ISLANDS TONIGHT. EXPECT ROUGH AND HAZARDOUS SURF CONDITIONS AS THE LEADING EDGE OF THE SWELL TRAIN REACHES SHORE. SEAS OF 8 FT OR GREATER ASSOCIATED WITH THIS SWELL WILL REACH ALL THE WAY TO 110W BY SAT MORNING.

GULF OF PANAMA...A TIGHT PRES GRADIENT WILL REMAIN IN PLACE ACROSS THE REGION DUE TO HIGH PRES RIDGING ACROSS THE WESTERN CARIBBEAN AND LOW PRES OVER NW COLOMBIA. THIS SETUP WILL CONTINUE TO SUPPORT FRESH TO STRONG NORTHERLY FLOW DOWNWIND OF THE GULF OF PANAMA THROUGH THE UPCOMING WEEKEND...OCCASIONALLY INCREASING TO 30 KT NEAR OR JUST S OF THE AZUERO PENINSULA DURING THE OVERNIGHT HOURS. SEAS WILL BUILD TO 7-10 FT ACROSS THIS AREA AS A RESULT.

GULF OF CALIFORNIA...MAINLY MODERATE NORTHERLY FLOW AND 1-3 FT SEAS WILL PREVAIL THROUGH SUN MORNING WITH SEAS OF 3-5 FT NEAR THE ENTRANCE.

$$ GR

Home