000 AXPZ20 KNHC 080940 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC FRI JUL 8 2011 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 0900 UTC. ...SPECIAL FEATURE... TROPICAL STORM CALVIN IS LOCATED NEAR 16.3N105.9W AT 0900 UTC MOVING W-NW OR 285 DEGREES AT 13 KT. MAXIMUM SUSTAINED WINDS ARE 45 KT WITH GUSTS TO 55 KT. NUMEROUS MODERATE TO STRONG CONVECTION IS LOCATED WITHIN 150 NM OF THE CENTER. SEE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP3/WTPZ23 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... DISCONTINUOUS MONSOON TROUGH AXIS FROM 10N85W TO 16N96W AND FROM 13N106W TO 09N114W THEN ITCZ TO 09N129W TO BEYOND 05N140W. SCATTERED MODERATE CONVECTION WITHIN 90 NM OF MONSOON TROUGH AXIS BETWEEN 85W AND 96W. ...DISCUSSION... A SCATTEROMETER PASS AT 0344 UTC MEASURED THE WIND FIELD ON THE EAST SIDE OF TROPICAL STORM CALVIN...AND WAS USED TO CALIBRATE GFS MODEL GUIDANCE FOR WINDS AND SEAS NEAR THE TROPICAL CYCLONE. UNIFORMLY COLD CLOUD TOPS FROM INTENSE CONVECTION NEAR THE CENTER OF T.S. CALVIN ARE MASKING THE LOW LEVEL FEATURES ASSOCIATED WITH IT. CALVIN IS EXPECTED TO INTENSIFY OVER THE NEXT 24 HOURS AS IT CONTINUES TO MOVE W-NW BEFORE ENCOUNTERING COLDER SEA SURFACE TEMPERATURES NW OF 18N110W WHICH SHOULD CAUSE IT WEAKEN RAPIDLY THIS WEEKEND. GRADIENT BETWEEN STRONG HIGH PRES CENTERED NW OF THE AREA NEAR 36N149W LOWER PRES ASSOCIATED WITH THE ITCZ IS SUPPORTING FRESH TO STRONG NE WINDS OVER THE EXTREME NW PORTION AREA NW OF A LINE FROM 30N129W TO 20N140W. WINDS ARE FORECAST TO DIMINISH BELOW 20 KT BY SAT NIGHT...WITH SEAS DIMINISHING BELOW 8 FT EARLY SUN AS THE HIGH PRES WEAKENS AND A NEW HIGH PRES CENTERED NEAR 38W157W BECOMES DOMINANT. CROSS-EQUATORIAL SW SWELLS WILL PREVAIL OVER THE DEEP TROPICS S OF 10N BETWEEN 95W AND 135W THROUGH THE WEEKEND. WAVE HEIGHTS ARE EXPECTED TO REACH 11 FT AS THE SWELLS CONTINUE TO PROPAGATE INTO THE AREA FROM THE SOUTHERN HEMISPHERE. $$ MUNDELL 000 AXPZ20 KNHC 080940 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC FRI JUL 8 2011 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 0900 UTC. ...SPECIAL FEATURE... TROPICAL STORM CALVIN IS LOCATED NEAR 16.3N105.9W AT 0900 UTC MOVING W-NW OR 285 DEGREES AT 13 KT. MAXIMUM SUSTAINED WINDS ARE 45 KT WITH GUSTS TO 55 KT. NUMEROUS MODERATE TO STRONG CONVECTION IS LOCATED WITHIN 150 NM OF THE CENTER. SEE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP3/WTPZ23 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... DISCONTINUOUS MONSOON TROUGH AXIS FROM 10N85W TO 16N96W AND FROM 13N106W TO 09N114W THEN ITCZ TO 09N129W TO BEYOND 05N140W. SCATTERED MODERATE CONVECTION WITHIN 90 NM OF MONSOON TROUGH AXIS BETWEEN 85W AND 96W. ...DISCUSSION... A SCATTEROMETER PASS AT 0344 UTC MEASURED THE WIND FIELD ON THE EAST SIDE OF TROPICAL STORM CALVIN...AND WAS USED TO CALIBRATE GFS MODEL GUIDANCE FOR WINDS AND SEAS NEAR THE TROPICAL CYCLONE. UNIFORMLY COLD CLOUD TOPS FROM INTENSE CONVECTION NEAR THE CENTER OF T.S. CALVIN ARE MASKING THE LOW LEVEL FEATURES ASSOCIATED WITH IT. CALVIN IS EXPECTED TO INTENSIFY OVER THE NEXT 24 HOURS AS IT CONTINUES TO MOVE W-NW BEFORE ENCOUNTERING COLDER SEA SURFACE TEMPERATURES NW OF 18N110W WHICH SHOULD CAUSE IT WEAKEN RAPIDLY THIS WEEKEND. GRADIENT BETWEEN STRONG HIGH PRES CENTERED NW OF THE AREA NEAR 36N149W LOWER PRES ASSOCIATED WITH THE ITCZ IS SUPPORTING FRESH TO STRONG NE WINDS OVER THE EXTREME NW PORTION AREA NW OF A LINE FROM 30N129W TO 20N140W. WINDS ARE FORECAST TO DIMINISH BELOW 20 KT BY SAT NIGHT...WITH SEAS DIMINISHING BELOW 8 FT EARLY SUN AS THE HIGH PRES WEAKENS AND A NEW HIGH PRES CENTERED NEAR 38W157W BECOMES DOMINANT. CROSS-EQUATORIAL SW SWELLS WILL PREVAIL OVER THE DEEP TROPICS S OF 10N BETWEEN 95W AND 135W THROUGH THE WEEKEND. WAVE HEIGHTS ARE EXPECTED TO REACH 11 FT AS THE SWELLS CONTINUE TO PROPAGATE INTO THE AREA FROM THE SOUTHERN HEMISPHERE. $$ MUNDELL