000 AXPZ20 KNHC 211505 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC THU AUG 21 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1415 UTC. ...SPECIAL FEATURES... TROPICAL STORM LOWELL WAS UPGRADED TO HURRICANE AT 21/1500 UTC. HURRICANE LOWELL IS CENTERED NEAR 20.0N 122.2W AT 21/1500 UTC MOVING NW AT 3 KT. ESTIMATED MINIMUM CENTRAL PRESSURE 982 MB. MAXIMUM SUSTAINED WINDS 65 KT WITH GUSTS TO 80 KT. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM W SEMICIRCLE AND WITHIN 180 NM NE QUADRANT OF CENTER. ISOLATED MODERATE CONVECTION IS WITHIN 210 NM SE QUADRANT OF CENTER. LOWELL REMAINS A VERY LARGE CIRCULATION WITH TROPICAL STORM FORCE WINDS EXTENDING FAR FROM THE CENTER. A SLOW WEAKENING IS EXPECTED TO BEGIN TONIGHT AND CONTINUE THROUGH SATURDAY. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC FOR MORE DETAILS. TROPICAL STORM KARINA CENTERED NEAR 15.0N 136.9W AT 21/1500 UTC OR ABOUT ABOUT 1075 NM E OF HILO HAWAII MOVING S AT 2 KT. ESTIMATED MINIMUM CENTRAL PRESSURE 999 MB. MAXIMUM SUSTAINED WINDS 50? KT WITH GUSTS TO 60 KT. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 150 NM SW QUADRANT OF CENTER. KARINA IS EXPECTED TO BEGIN WEAKENING IN A DAY OR SO. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP1/WTPZ21 KNHC FOR MORE DETAILS. A 1007 MB LOW IS NEAR 10N96W MOVING SLOWLY W WITH A TROUGH AXIS EXTENDING NORTHWARD TO THE W GULF OF TEHUANTEPEC NEAR 16N96W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM OF THE LOW CENTER. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION COVERS THE REMAINDER OF THE AREA WITHIN 75 NM OF LINE FROM 10N90W TO 15N96W AND FROM 11N-16N BETWEEN 96W-101W. ENVIRONMENTAL CONDITIONS ARE CONDUCIVE FOR TROPICAL DEVELOPMENT AND THE LOW HAS A HIGH PROBABILITY OF TROPICAL CYCLONE FORMATION DURING THE NEXT 48 HOURS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH EXTENDS FROM 7N77W ALONG 6N86W TO 1007 MB LOW NEAR 10N96W THEN 9N103W TO 11N113W. SCATTERED STRONG CONVECTION IS WITHIN 75 NM OF THE MONSOON TROUGH BETWEEN 78W-81W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 330 NM OF MONSOON TROUGH BETWEEN 99W-112W. SCATTERED MODERATE CONVECTION IS WITHIN 180 NM N OF MONSOON TROUGH BETWEEN 82W AND 87W. ...DISCUSSION... A SURFACE RIDGE EXTENDS SE FROM SUBTROPICAL HIGH N-NW OF THE AREA NEAR 40N143W THROUGH 32N132W TO BAJA CALIFORNIA NEAR 29N115W. THE RIDGE HAS BEEN SHIFTING NORTHWARD AHEAD OF LOWELL...AND SUPPORTS MODERATE WINDS W OF 110W OUTSIDE OF KARINA AND LOWELL INFLUENCE. PRESSURE GRADIENT WILL TIGHTEN OVER THE NW CORNER OF THE AREA TONIGHT AND FRI AS LOWELL MOVES UP AGAINST THE RIDGE...WITH FRESH TO STRONG NE WINDS DEVELOPING AND SEAS BUILDING TO 9 FT IN FAR NW PORTION. AN AREA OF MIXED S AND SW SWELL WILL APPROACH THE EQUATOR SW OF THE GALAPAGOS ISLANDS...AND NUDGE INTO FORECAST WATERS SOUTH OF 02S W OF 100W. $$ PAW