Tropical Weather Discussion
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000
AXPZ20 KNHC 122121
TWDEP

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT JUL 12 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2100 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE AXIS EXTENDS FROM THE WESTERN YUCATAN PENINSULA
S INTO THE PACIFIC TO 09N91W MOVING W AT AROUND 20 KT. THERE IS
NO SIGNIFICANT CONVECTION ASSOCIATED WITH THE WAVE...HOWEVER IT
IS HELPING TO BOOST GAP WIND EVENTS IN THE GULF OF TEHUANTEPEC
DISCUSSED MORE BELOW.

A TROPICAL WAVE AXIS EXTENDS FROM 09N123W TO 19N122W MOVING W AT
AROUND 20 KT. THIS WAVE HAS HELPED FOR A NORTHWARD PERTURBATION
TO THE ITCZ. ACTIVE CONVECTION ASSOCIATED TO THE WAVE IS FOUND
IN THE VICINITY OF THE SOUTHERN PORTION OF THE WAVE ALONG THE
ITCZ.

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

THE MONSOON TROUGH AXIS EXTENDS FROM 08N77W TO 08N94W TO
06N108W. ITCZ AXIS EXTENDS FROM 06N108W TO 11N121W TO 10N130W
THEN RESUMES FROM 06N138W TO BEYOND 05N140W. SCATTERED MODERATE
TO STRONG CONVECTION IS WITHIN 300 NM S OF THE AXIS BETWEEN 80W
AND 93W. SCATTERED MODERATE CONVECTION IS WITHIN 240 NM NE OF A
LINE FROM 06N103W TO 10N107W...AND FROM 07N TO 10N BETWEEN 120W
AND 130W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS
FROM 10N TO 13N BETWEEN 125W AND 132W.

...DISCUSSION...

1024 MB HIGH PRES CENTERED N OF THE AREA NEAR 34N133W EXTENDS A
RIDGE SE TO NEAR THE SOUTHERN TIP OF THE BAJA CALIFORNIA
PENINSULA AT 21N110W. THE PRESSURE GRADIENT BETWEEN THE RIDGING
AND LOWER PRESSURES IN THE VICINITY OF THE ITCZ IS MAINTAINING
MAINLY GENTLE TO MODERATE TRADES OVER THE WATERS W OF 110W. AN
EXCEPTION IS ALONG AND JUST W OF THE BAJA CALIFORNIA PENINSULA N
OF 26N WHERE ASCAT AND ASCAT-B SCATTEROMETER DATA SHOW FRESH NW-
N WINDS WITH A TIGHT PRESSURE GRADIENT IN PLACE DUE TO SURFACE
TROUGHING IN THE VICINITY OF THE GULF OF CALIFORNIA.

THE RIDGING WILL STRENGTHEN OVER THE WESTERN WATERS DURING THE
NEXT 24 HOURS WHICH WILL RESULT IN A TIGHTENING PRESSURE
GRADIENT AS A TROPICAL WAVE MENTIONED ABOVE MOVES THROUGH THE W
CENTRAL WATERS. NE-E WINDS WILL INCREASE TO FRESH LEVELS AHEAD
OF THE WAVE WHICH WILL SUPPORT COMBINED SEAS OF 8-9 FT N OF THE
ITCZ W OF THE WAVE AXIS BY SUN AFTERNOON THROUGH MON AFTERNOON.

GAP WINDS...
THE TROPICAL WAVE OVER THE EASTERN WATERS HAS HELPED FOR A
RELATIVELY RARE STRONG SUMMER TIME GAP WIND EVENT THROUGH THE
GULFS OF PAPAGAYO AND TEHUANTEPEC WITH WINDS REACHING NEAR GALE
FORCE OVER THESE EARLY THIS MORNING. WINDS ARE NOW DIMINISHING
OVER THE GULF OF PAPAGAYO AS THIS TROPICAL WAVE MOVES FURTHER
WESTWARD AWAY FROM THE AREA...HOWEVER ANOTHER TROPICAL WAVE
CURRENTLY IN THE WESTERN CARIBBEAN SEA WILL HELP ENHANCE ANOTHER
FRESH TO STRONG GAP WIND EVENT IN PAPAGAYO TONIGHT. MEANWHILE
NEAR GALE FORCE WINDS WILL CONTINUE OVER THE GULF OF TEHUANTEPEC
OVER THE NEXT 12-24 HOURS AS THE TROPICAL WAVE CONTINUES EAST OF
THIS AREA AND HELPS TO INDUCE THE NE FLOW THROUGH THE GAP. WINDS
WILL START TO DIMINISH SUN AS THE WAVE PASSES WEST OF THE GULF
OF TEHUANTEPEC...AND WILL DECREASE TO 20 KT OR LESS OVER THE
AREA BY MON AFTERNOON.

$$
LEWITSKY


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