Home


000
AXPZ20 KNHC 301556
TWDEP

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN AUG 30 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 1545 UTC.


...SPECIAL FEATURE...

HURRICANE JIMENA IS CENTERED NEAR 14.2N 129.6W OR ABOUT 1725 MILES E OF HILO HAWAII AT 1500 UTC. ALTHOUGH THE 10 NM WIDE EYE HAS BEEN UNDERGOING REPLACEMENT CYCLES...AND CONTINUES TO WOBBLE DUE TO PRONOUNCED TROCHOIDAL OSCILLATION...THE GENERAL MOTION IS W-NW OR 295 DEG AT 12 KT...AND THIS GENERAL MOTION IS EXPECTED FOR THE NEXT COUPLE OF DAYS ALONG THE W PERIPHERY OF A SUB- TROPICAL RIDGE. ESTIMATED MINIMUM CENTRAL PRESSURE IS 949 MB. THE MAXIMUM SUSTAINED WINDS ARE 115 KT WITH GUSTS TO 140 KT AND JIMENA IS FORECAST TO REMAIN A MAJOR HURRICANE THROUGH MON...THEN A WEAKENING TREND IS ANTICIPATED. CURRENTLY NUMEROUS MODERATE ISOLATED STRONG CONVECTION IS OBSERVED WITHIN 90 NM NE AND WITHIN 60 NM SW SEMICIRCLES OF CENTER. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED IN BANDS ELSEWHERE WITHIN 210 NM OF THE CENTER. JIMENA IS PRODUCING A LARGE AREA 12 FT OR GREATER SEAS OUTWARD TO 290 NM N AND 240 NM S OF THE CENTER WITH SURROUNDING AREA TO 20-33 KT WINDS AND SEAS OF 8-11 FT ARE EXPECTED TO EXPANDING TO ABOUT 300 OF THE CENTER. REFER TO THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP3/WTPZ23 KNHC AND HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFEPI/FZPN02 KWBC FOR ADDITIONAL DETAILS

A 1009 MB SURFACE LOW IS EMBEDDED IN THE MONSOON TROUGH NEAR 10N108.5W AND IS MOVING W AT ABOUT 5 KT. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED WITHIN 270 NM OVER THE E SEMICIRCLE AND WITHIN 180 NM W SEMICIRCLE OF THE CENTER. THE GRADIENT HAS TIGHTENED E OF THE LOW ENHANCING THE SOUTHWESTERLY MONSOONAL FLOW TO 20 KT WITHIN ABOUT 300 NM OVER THE SE SEMICIRCLE WITH COMBINED SEAS OF 7-8 FT. CONDITIONS ARE FAVORABLE FOR TROPICAL FORMATION AND THIS LOW MOVES SLIGHTLY N OF DUE W TO NEAR 105N112.5W ON MON AND NEAR 11N116W ON TUE.


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

THE MONSOON TROUGH EXTENDS W-SW OFF THE PACIFIC COAST OF COLOMBIA AT 07N78W TO TO 07N80W...THEN TURNS NW 10N88W....THEN SW TO 08N97W...THEN TURNS NW AGAIN TO THE EMBEDDED LOW PRES NEAR 10N108.5W...CONTINUING SW 09N114W THEN NW AGAIN TO 11N118W WHERE IT LOSES IDENTITY. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 180 NM EITHER SIDE OF A LINE FROM 04.5N80W TO 14.5N96W...ELSEWHERE WITHIN 180 NM OF LINE FROM 05N96W TO 12N106W TO 08N116W...AND WITHIN 30 NM EITHER SIDE OF A LINE FROM 10N126W TO 05N140W.

SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED OVER AND WITHIN 75 NM OF THE PACIFIC COAST OF MAINLAND MEXICO FROM 19-24N.


...DISCUSSION...

A SURFACE RIDGE EXTENDS SE FROM 32N136W TO 17N104W. THE GRADIENT IS SUPPORTING 15-20 KT TRADES ACROSS THE WATERS S OF THE RIDGE WITH COMBINED SEAS OF 6-8 FT IN MIXED NW AND CROSS EQUATORIAL S SWELL. LITTLE CHANGE EXPECTED THROUGH TUE THEN THESE CONDITIONS WILL SHIFT WESTWARD AS JIMENA CROSSES 140W ON WED. THE GRADIENT E OF THE RIDGE IS SUPPORTING NW 15-20 KT WINDS ACROSS THE SUBTROPICS E OF 122W TO THE BAJA CALIFORNIA PENINSULA WITH COMBINED SEAS OF 6-8 FT ACROSS THE DISCUSSION. THE GRADIENT WILL RELAX ON MON INTO TUE WITH SEAS SUBSIDING TO 4-7 FT BY TUE EVENING.

GULF OF TEHUANTEPEC...A 20-25 KT NORTHERLY SURGE LAST NIGHT WILL DIMINISH TO 15-20 KT BY EARLY THIS AFTERNOON WITH THE 5-8 FT SEAS OBSERVED AT SUNRISE THIS MORNING SUBSIDING TO 4-6 FT LATE TODAY. TONIGHTS DRAINAGE IS EXPECTED TO MAX AT 15 KT WITH SEAS BUILDING TO 6 FT.

$$ NELSON

Home