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AXPZ20 KNHC 250945
TWDEP

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON MAY 25 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0945 UTC.


...TROPICAL LOWS...

A 1010 MB LOW PRESSURE IS ANALYZED NEAR 08N121W AND IS MOVING W AT ABOUT 15 KT. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED OVER ITS N SEMICIRCLE...FROM 08-13N BETWEEN 115-124W. THIS LOW IS FORECAST TO CONTINUE W AND GRADUALLY LOSE IDENTITY BY MID WEEK.

A 1009 MB LOW PRES IS OBSERVED NEAR 12.5N132W AND IS MOVING JUST N OF DUE W AT ABOUT 7 KT. THE LOW LEVEL CENTER WAS EXPOSED ON THE LAST VISIBLE SATELLITE IMAGERY ON SUN EVENING WITH SCATTERED MODERATE ISOLATED STRONG CONVECTION WELL E OF THE CENTER FROM 10- 15N BETWEEN 125-131W DUE TO STRONG WESTERLY SHEAR. THE POTENTIAL FOR TROPICAL CYCLONE DEVELOPMENT IS BECOMING LESS LIKELY WITH TIME...AND EXPECT THIS LOW TO WEAKEN TO AN OPEN TROUGH FROM 16N135W TO 12N134W TO 09N140W LATE TONIGHT. ASSOCIATED WINDS HAS DIMINISHED TO 15-20 KT. COMBINED SEAS OF 7-9 FT CURRENTLY OBSERVED WITHIN 390 NM OVER THE NW SEMICIRCLE WILL SUBSIDE TO LESS THAN 8 FT ON TUE.


...TROPICAL WAVES...

A TROPICAL WAVE EXTENDS FROM 02N84W TO 11N86W WITH A 1010 MB LOW PRESSURE ALONG THE WAVE AXIS AT 09N86W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 120 NM OF COAST OF CENTRAL AMERICA FROM 78W TO 86W.

A TROPICAL WAVE WAS ANALYZED FROM 02N102W TO 13N101W AND IS MOVING W AT ABOUT 12 KT. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED FROM 02-08N BETWEEN 92-103W. LOW PRESSURE IS FORECAST TO SOON DEVELOP ALONG THIS TROPICAL WAVE. THE GRADIENT WILL INCREASE OVER THE SE SEMICIRCLE OF THE LOW AROUND MID WEEK WITH THE POSSIBILITY FOR TROPICAL CYCLONE DEVELOPMENT INCREASING LATE IN THE WEEK.


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

A KELVIN WAVE HAS MOVED INTO THE DEEP TROPICS W OF 115W AND HAS DISRUPTED THE LOW LEVEL WINDS. CURRENTLY THERE IS NOT A WELL DEFINED MONSOON TROUGH OR ITCZ.

SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED ACROSS THE DEEP TROPICS WITHIN 60 NM EITHER SIDE OF LINES FROM 01N85W TO 07N90W...AND FROM 01N103W TO 05N116W.

A SURFACE LOW IS ANALYZED OVER THE CARIBBEAN COAST OF COLOMBIA NEAR 10N75W AND TRAILS A SURFACE TROUGH SW ALONG THE PACIFIC COAST OF COLOMBIA TO NEAR 03.5N78W. CONVECTION HAS BEEN FLARING INTERMITTENTLY ALONG THIS TROUGH BUT IS CURRENTLY SUPPRESSED AND ONLY A FEW SMALL CLUSTERS OF MODERATE CONVECTION IS NOTED ALONG THE PACIFIC COAST OF COLOMBIA.


...DISCUSSION...

AN UPPER CYCLONE IS W OF THE AREA NEAR 31N143W WITH AN UPPER TROUGH EXTENDING S TO BASE NEAR 20N140W. ALTHOUGH AN ASSOCIATED SURFACE FRONTAL TROUGH WILL ADVANCE SLOWLY E AND DISSIPATE ALONG 140W LATER TODAY...THE GRADIENT IS SUPPORTING SE 20-25 KT WINDS AND 7-9 FT SEAS ACROSS THE DISCUSSION WATERS FROM 29-32N W OF 136W. THE GRADIENT WILL RELAX TODAY WITH WINDS DIMINISHING TO SE AT 15-20 KT...AND THE ASSOCIATED SEAS ARE EXPECTED TO SUBSIDE TO 5-7 FT LATE TONIGHT.

AN UPPER TROUGH EXTENDS S ACROSS MEXICO ALONG 108W TO BASE OVER THE EPAC NEAR 18N107W...AND CONTINUES TO ADVECT VERY DRY UPPER AIR SE ACROSS THE SUBTROPICS BETWEEN 117-102W.

AN UPPER ANTICYCLONE IS CENTERED OVER THE TROPICS NEAR 14N117W WITH AN UPPER RIDGE EXTENDING W TO BEYOND 10N140W. AN UPPER RIDGE ALSO EXTENDS NW TO BEYOND 32N129W AND SEPARATES THE AREAS OF UPPER CYCLONIC FLOW PREVIOUSLY DESCRIBED. UPPER MOISTURE IS ADVECTED ACROSS THE RIDGE CREST TO ALONG 120W. SOME OF THIS MOISTURE MAY REACH THE CENTRAL BAJA PENINSULA LATE TONIGHT AS THE BAND OF DRY UPPER AIR SHIFTS EASTWARD.

AN UPPER ANTICYCLONE OVER COLOMBIA RIDGES WNW TO A CREST NEAR 10N103W AND IS ENHANCING THE CONVECTION OVER THE SE TROPICAL AREA AS PREVIOUSLY DESCRIBED. SOME OF THE DEBRIS MOISTURE IS ADVECTED NE ACROSS THE SOUTHERN CARIBBEAN AND SOME OF THE MOISTURE IS SPREADING S ACROSS THE EQUATOR BETWEEN 80-120W.

A SURFACE RIDGE EXTENDS FROM 32N131W TO 15N100W. TO THE NE OF THE RIDGE ARE NW WINDS AT 10-15 KT WITHIN ABOUT 180 NM W OF THE PACIFIC COAST OF THE BAJA PENINSULA WITH COMBINED SEAS OF 3-5 FT. LITTLE CHANGE EXPECTED THROUGH THU NIGHT...THEN THE GRADIENT SHOULD FURTHER RELAX ON FRI SUPPORTING NW WINDS AT 10 KT WITH SEAS SUBSIDING TO 3-4 FT.

GULF OF PAPAGAYO...CURRENTLY ENE 20-25 KT WINDS SHOULD DIMINISH AFTER SUNRISE THIS MORNING...THEN EXPECT NOCTURNAL 15-20 KT PULSES THE REMAINDER OF THE WEEK.

$$ NELSON

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