000
AXPZ20 KNHC 230921
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
1005 UTC FRI AUG 23 2013

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 
0300 UTC.
                                    
...SPECIAL FEATURES... 
TROPICAL DEPRESSION NINE-E CENTERED NEAR 18.7N 112.9W AT 0900 
UTC OR 350 NM SW OF CABO SAN LUCAS MEXICO MOVING NW AT 6 KT. 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB. MAXIMUM SUSTAINED 
WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. NUMEROUS MODERATE TO 
STRONG FROM 15N TO 19N BETWEEN 113W AND 117W. CLUSTER OF 
MODERATE TO STRONG CONVECTION E OF CENTER FROM 16N TO 20N 
BETWEEN 107W AND 112W. SEE LATEST NHC FORECAST/ADVISORY UNDER 
AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. 

THE DEPRESSION HAS A SHORT WINDOW OF TIME TO STRENGTHEN WITH 
SSTS SIGNIFICANTLY DROPPING IN 48 HOURS OR LESS AS IT CONTINUES 
TO THE NW. THE LATEST FORECAST HAS THE DEPRESSION STRENGTHENING 
TO A TROPICAL STORM BY THIS AFTERNOON THEN WEAKENING TO A 
REMNANT LOW BY SAT NIGHT. A LONG FETCH OF SW WINDS ASSOCIATED 
WITH THE DEPRESSION ARE LIKELY TO BUILD SEAS MUCH HIGHER THAN 
USUAL WITH THE POTENTIAL TO HEAVILY IMPACT THE SOUTHERN HALF OF 
BAJA CALIFORNIA COAST INCLUDING THE SOUTHERN GULF OF CALIFORNIA 
AS AN ASSOCIATED LARGE SOUTHERLY SWELL IS FORCED TO FUNNEL INTO 
THE GULF. MAXIMUM SEAS ARE ALREADY 15 FT WITH 12 FT SEAS 
EXTENDING TO WITHIN 210 NM SE AND 150 NM SW QUADRANTS. TROPICAL 
MOISTURE MAY SURGE NORTHWARD TOWARD NW MEXICO FROM DAYS 3-5 
INTRODUCING THE POSSIBILITY OF HEAVY RAINS AND FLASH FLOODING.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...       
MONSOON TROUGH FROM 10N85W TO 1009 MB LOW PRES 10N90W TO 8N102W 
THEN RESUMES AT 17N117W TO 1008 MB LOW PRES NEAR 15N120W TO 
10N140W. NUMEROUS MODERATE TO STRONG WITHIN 260 NM N OF AXIS 
FROM 87W TO 92W. SCATTERED MODERATE ISOLATED STRONG WITHIN 100 
NM S OF AXIS FROM 120W TO 129W.

...DISCUSSION...
UPPER LEVEL RIDGE OVER THE FAR NW PORTION OF THE DISCUSSION AREA 
EXTENDING FROM AN ANTICYCLONIC CIRCULATION W OF THE AREA NEAR 
20N144W TO 30N130W. DOWNSTREAM SHARP UPPER LEVEL TROUGH EXTENDS 
FROM 32N120W TO 18N127W. MODERATE TO STRONG SUBSIDENCE WITH DRY 
AND STABLE AIR AT THE MIDDLE AND UPPER LEVELS IS N OF 20N W OF 
120W. ANOTHER UPPER LEVEL ANTICYCLONIC CIRCULATION IS OVER 
SOUTHERN BAJA CALIFORNIA NEAR 20N111W. UPPER LEVEL DIFFLUENT 
FLOW IS PROVIDING FOR GOOD OUTFLOW OVER TROPICAL DEPRESSION 
NINE-E. 

A BROAD SURFACE RIDGE IS NW OF TROPICAL DEPRESSION NINE-E WITH NE
WINDS 10-15 KT IN THE AREA. 

WEAK 1009 MB LOW PRES IS EMBEDDED IN THE MONSOON TROUGH SW OF 
NINE-E NEAR 15N120W. THIS LOW HAS STALLED AND REMAINS UNDER GOOD 
OUTFLOW ALOFT. WHILE THE LOW CONTINUES TO CARRY A LOW CHANCE OF 
TROPICAL DEVELOPMENT IT WILL NEVERTHELESS MAINTAINS FRESH TO 
STRONG SW WINDS IN ITS SE QUADRANT EXTENDING THE FETCH REGION OF 
SW-S WINDS FUNNELING INTO NINE-E. AS NOTED ABOVE EXTENSIVE FETCH 
WILL CONTRIBUTE AND BUILD HIGHER SEAS THAN NORMAL HEADED TOWARDS 
BAJA CALIFORNIA.

A TROPICAL WAVE IN THE W CARIBBEAN WILL  MOVE OVER THE YUCATAN 
PENINSULA AND GUATEMALA LATE LATE TODAY SHIFTING WINDS TO THE N 
AND NE...AND FORCING FLOW THROUGH THE THE GULF OF TEHUANTEPEC AS 
FRESH STRONG NORTHERLY WINDS. SEAS WILL BE NEAR 8 FT ALONG WITH 
THESE WINDS. THE WIND FLOW WILL SHIFT BACK TO THE SE WHEN WAVE 
MOVES W OF THE GULF OF TEHUANTEPEC BY LATE SAT. 
 
$$
DGS