000
AXPZ20 KNHC 300331
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED JAN 30 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

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

THE MONSOON TROUGH IS ALONG 04N77W TO 09N84W TO 04N94W. THE 
INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 04N94W TO 
05N115W TO 04N130W TO 05N140W. NO SIGNIFICANT CONVECTION.

...DISCUSSION...

AN UPPER LEVEL TROUGH HAS AN AXIS FROM S CENTRAL NEW MEXICO TO 
ACROSS NW MEXICO NEAR 30N110W TO 27N128W TO 11N140W. MOISTURE IS 
BEING ADVECTED TO THE NE BY A 80-100 KT JET CORE JUST E OF THE 
SW HALF OF THE TROUGH...INCREASING TO 100-135 KT OVER THE NE 
HALF OF THE TROUGH...FROM THE DEEP TROPICS WITHIN 420-600 NM E 
OF THE UPPER TROUGH AXIS. AN UPPER LEVEL RIDGE IS SE OF THE 
TROUGH EXTENDING FROM SOUTHERN MEXICO NEAR THE GULF OF 
TEHUANTEPEC AREA TO THE SW NEAR 00N112W. AN UPPER LEVEL CYCLONIC 
CIRCULATION IN THE DEEP TROPICS IS CENTERED NEAR 05N93W WITH AN 
ATTENDANT TROUGH REACHING FROM SOUTHERN GUATEMALA THROUGH THE 
CYCLONIC CENTER TO ACROSS THE GALAPAGOS ISLANDS WELL INTO THE 
SOUTHERN HEMISPHERE.

AT THE SURFACE...A RIDGE EXTENDS FROM NEARLY STATIONARY 1039 MB 
HIGH PRES WELL N OF THE AREA NEAR 38N133W TO THE SE THROUGH 
30N130W WITH A TERMINUS NEAR 11N100W. THE PRES GRADIENT ON THE 
SOUTHERN PERIPHERY OF THE RIDGE IS SUPPORTING FRESH TO STRONG 
TRADES ACROSS ROUGHLY THE NW HALF OF THE DISCUSSION WATERS. SEAS 
OF 8-13 FT CURRENTLY ACCOMPANY THESE WINDS...ABOUT 1-2 FT HIGHER 
THAN THE WAVEWATCH MODEL GUIDANCE AS INDICATED BY EARLIER 
ALTIMETER PASSES AND SHIP OBSERVATIONS. THE RIDGE WILL WEAKEN 
SIGNIFICANTLY DURING THE NEXT 24-48 HOURS ALLOWING FOR WINDS TO 
DIMINISH TO 20 KT OR LESS BY THU EVENING WITH REMNANT SEAS 
SUBSIDING TO 8-11 FT BY THEN.

BROAD TROUGHING WILL SET UP OVER WESTERN MEXICO AND THIS 
COMBINED WITH THE RIDGE TO THE SW-W WILL FEED NW-N FRESH TO 
STRONG WINDS FIRST IN THE SOUTHERN GULF OF CALIFORNIA...
EXPANDING TO ENCOMPASS ESSENTIALLY THE ENTIRE GULF BY WED 
EVENING. AS THIS OCCURS SEAS OF 8-10 FT WILL SPILL OUT OF THE 
SOUTHERN GULF TO 19N. THESE WINDS WILL GRADUALLY WEAKEN TO 20 KT 
OR LESS JUST BEYOND 48 HOURS AS THE PRES GRADIENT WEAKENS.

GAP WINDS...A STRONG COLD FRONT WILL RUSH THROUGH THE GULF OF 
MEXICO ON WED WITH A SURGE OF NORTHERLY WINDS FOLLOWING THE 
FRONT FUNNELING THROUGH THE CHIVELA PASS TO THE GULF OF 
TEHUANTEPEC AREA. THESE WINDS ARE FORECAST TO RAPIDLY REACH GALE 
FORCE BY WED NIGHT...UP TO 45 KT LATE WED NIGHT INTO EARLY THU 
MORNING...WITH GALE CONDITIONS PERSISTING THROUGH AT LEAST THU 
NIGHT. STRONG HIGH PRES BUILDING IN BEHIND THE FRONT WILL ALSO 
HELP TO MAINTAIN THESE CONDITIONS. CURRENT MODEL GUIDANCE (10M 
WINDS) IS CAPPED AT 45 KT ALTHOUGH THERE EXISTS A POSSIBILITY 
FOR MINIMAL STORM FORCE WINDS (30M GUIDANCE WINDS ARE UP TO 
50-65 KT) WHICH WILL NEED TO BE MONITORED IN CASE THE WARNING 
NEEDS TO BE UPGRADED PRIOR TO THE EVENT.

NE-E 20-25 KT WINDS WILL CONTINUE TO PULSE IN THE GULF OF 
PAPAGAYO DURING THE NEXT FEW DAYS...WITH THE STRONGEST WINDS 
OCCURRING DURING THE LATE NIGHT AND EARLY MORNING HOURS WITH 
ENHANCED DRAINAGE FLOW...AND WEAKER WINDS DURING THE AFTERNOONS.

FRESH TO STRONG WINDS WILL SPREAD ACROSS THE ISTHMUS OF PANAMA 
TO THE GULF OF PANAMA BY THU EVENING FROM THE SW CARIBBEAN 
SEA...BUILDING SEAS TO UP TO 9 FT DOWNWIND OF THE GULF BY FRI.

$$
LEWITSKY