| HOME | ARCHIVES | FORECASTS | IMAGERY | ABOUT NHC | RECONNAISSANCE |

---

Eastern Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 300932
TWDEP 

TROPICAL WEATHER DISCUSSION                                   
NWS NATIONAL HURRICANE CENTER MIAMI FL                       
1005 UTC WED JUL 30 2014

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 
0830 UTC.

...TROPICAL WAVES...                                            
A TROPICAL WAVE IS ALONG 98W N OF 12N MOVING W AT 15-20 KT. A 
CLUSTER A MODERATE TO ISOLATED STRONG THE WAVE IS IN A FAVORABLE 
AREA FOR CONVECTIVE GROWTH ON THE SOUTHEAST SIDE OF AN UPPER LOW 
CENTERED NEAR 19N108W. SCATTERED MODERATE CONVECTION WITHIN 120 
NM W OF THE WAVE AXIS N OF 11N. 

A SECOND TROPICAL WAVE IS ALONG 118W FROM 11N TO 17N. A 1010 MB 
LOW PRES CENTER IS ALONG THE WAVE AXIS NEAR 11N118W. CONVERGENT 
NE TO E WINDS INTO THE EAST SIDE OF THE TROPICAL WAVE ARE 
CREATING A LINE OF MODERATE TO STRONG THUNDERSTORMS FROM 12N TO 
15N BETWEEN 105W AND 110W.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...           
THE MONSOON TROUGH EXTENDS FROM 09N79W TO LOW PRES NEAR 11N118W 
1010 MB TO LOW NEAR 11N118W 1010 MB. SCATTERED MODERATE TO 
STRONG CONVECTION IS OBSERVED WITHIN 120 NM S OF AXIS E OF 83W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED WITHIN 
60 NM SE QUADRANT OF LOW NEAR 11N118W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION IS OBSERVED FROM 05N TO 08N BETWEEN 
113W AND 123W. 

...DISCUSSION...

THE REMNANT LOW OF HERNAN IS ANALYZED AS A 1014 MB LOW PRES ON 
THE 0600 UTC SURFACE MAP NEAR 24N123W. AN ASCAT SATELLITE PASS 
FROM 0500 UTC INDICATED HERNAN IS STILL A CLOSED CIRCULATION 
WITH 20 TO 25 KT WINDS WITHIN 60 NM OF THE CENTER IN THE N 
QUADRANT OF THE LOW. THE LOW IS IN AN AREA OF STRONG SOUTHERLY 
SHEAR ON THE EAST SIDE OF A SHARP UPPER TROUGH EXTENDING FROM 
30N120W TO 17N125W. THE LAST ACTIVE CONVECTION ENDED SEVERAL 
HOURS AGO AND WAS DISPLACED WELL TO THE NORTH OF THE LOW LEVEL 
CENTER. THE LOW IS EXPECT TO CONTINUE ON A WESTERLY TRACK INTO 
MORE STABLE AIR AND COOLER WATER...BECOMING A WEAK TROUGH WITH 
THE NEXT 36 HOURS.

CONVECTION AROUND THE 1010 MB LOW PRES NEAR 11N118W IS BECOMING 
BETTER ORGANIZED. THE ASCAT SATELLITE PASS FROM 05 UTC INDICATED 
SOUTHERLY WINDS CONVERGING INTO THE LOW PRES FROM THE 
SOUTH...INITIATING A WELL DEFINED BAND OF CONVECTION FROM 05N TO 
08N BETWEEN 113W AND 123W. GLOBAL MODELS INCLUDING THE 
GFS...ECMWF AND UKMET INDICATE THIS LOW WILL CONTINUE TO DEVELOP 
OVER THE NEXT COUPLE OF DAYS AS IT TRACKS WESTWARD AND TROPICAL 
CYCLONE DEVELOPMENT IS POSSIBLE THROUGH EARLY NEXT WEEK.

A 1010 MB LOW PRES IS WITHIN THE ITCZ NEAR 11N130W. CONVECTION 
HAS DISSIPATED ALMOST ENTIRELY AROUND THIS LOW IN THE PAST SIX 
HOURS...ALTHOUGH A 0630 UTC ASCAT SATELLITE PASS INDICATED WINDS 
OF 20 TO 25 KT WITHIN 90 NM TO THE NORTH OF THE CENTER. NO 
SIGNIFICANT DEVELOPMENT IS EXPECT HOWEVER WITH THIS LOW OVER THE 
NEXT 48 HOURS AS DRY AIR ALOFT ON THE WEST SIDE OF THE UPPER 
TROUGH CONTINUES TO INHIBIT CONVECTIVE GROWTH.

ANOTHER 1011 MB LOW PRES IS LOCATED NEAR 15N139W. THE PRES 
GRADIENT BETWEEN THE LOW PRES AND A RIDGE OVER THE NW WATERS IS 
RESULTING IN AN AREA OF FRESH TO STRONG WINDS OF 20 TO 25 KT 
FROM 15N TO 20N W OF 135W WITH SEAS TO 9 FT. THE LOW IS 
CURRENTLY MOVING SLOWLY TO THE WEST OF 140W. WINDS AND SEAS WILL 
DIMINISH ACROSS THE FORECAST AREA THE NEXT 24 HOURS.  

FRESH TO STRONG WINDS WILL CONTINUE TO PULSE ACROSS THE GULF OF 
PAPAGAYO...PARTICULARLY DURING THE OVERNIGHT AND EARLY MORNING 
HOURS WITH THE ASSISTANCE OF THE NOCTURNAL DRAINAGE FLOW. AN 
ASCAT SATELLITE PASS FROM 03 UTC INDICATED AN AREA OF FRESH TO 
STRONG GAP WINDS EMERGING INTO THE GULF OF TEHUANTEPEC...LIKELY 
RELATED TO THE PASSAGE OF THE TROPICAL WAVE ALONG 98W. THESE 
WINDS WILL DIMINISH BELOW 20 KT THROUGH THIS MORNING.

$$ 
CHRISTENSEN