000
AXPZ20 KNHC 221604
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU APR 22 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1515 UTC.

...ITCZ...

AXIS WAS ANALYZED FROM 05N77W TO 05N80W TO 09N87W TO 05N102W TO 
11N119W TO 06N123W TO 07N130W TO 05N140W. SCATTERED MODERATE 
ISOLATED STRONG WITHIN 120 NM N AND 150 NM S OF AXIS BETWEEN 87W 
AND 92W. SCATTERED MODERATE TO STRONG WITHIN 150 NM N AND 120 NM 
S OF AXIS BETWEEN 99W AND 112W. SCATTERED TO NUMEROUS MODERATE 
TO STRONG FROM 04N TO 12N BETWEEN 112W AND 123W. 
 
...DISCUSSION...

A DEEP LAYERED CYCLONE WAS CENTERED NEAR 38N116W WITH MID/UPPER 
TROUGH AXIS EXTENDING S-SW TO NEAR 23N119W WHERE THE BASE OF 
TROUGH COVERED THE AREA BETWEEN 105W AND 128W. DEEP LAYERED 
MOISTURE CONTINUED TO CIRCULATE AROUND THE MAIN LOW WITHIN 450 
NM OF THE CENTER. TO THE S OF THIS MOISTURE...MID/UPPER 
CONVERGENCE ACROSS THE BROAD BASE OF THE TROUGH WAS YIELDING 
SUBSIDENCE AND STABLE CONDITIONS. 

W OF THIS CYCLONE AND N OF 28N WAS AN UPPER RIDGE EXTENDING W TO 
150W. A SUBTROPICAL JET COULD BE SEEN MOVING JUST S OF THE 
HAWAIIAN ISLANDS AND EXTENDING DUE E ALONG ABOUT 17N WHERE IT 
MERGED WITH A BROAD JET OCCURRING TO THE S OF THE BROAD TROUGH 
DESCRIBED ABOVE CONTINUING FROM 17N120W NEWD WHERE IT BECAME 
SOMEWHAT DIFFLUENT ACROSS CENTRAL MEXICO AND INTO THE GULF OF 
MEXICO. ACTIVE ITCZ CONVECTION BETWEEN 105W AND 125W CONTINUED 
TO AID IN THE MAINTENANCE OF A PERSISTENT BROAD AND FLAT UPPER 
RIDGE S OF THIS JET...AND 15N...BETWEEN 130W AND 105W. ABUNDANT 
UPPER LEVEL MOISTURE WAS BEING ADVECTED NE  AND ACROSS MEXICO. 

A MID/UPPER LEVEL CYCLONE WAS CENTERED ACROSS THE EQUATOR NEAR 
THE GALAPAGOS ISLANDS ALONG 92/93W...WHILE A LARGE AND BROAD 
UPPER RIDGE PERSISTED ACROSS THE TROPICAL ATLC ALONG 11/12N 
EXTENDING W THE PANAMA AND COSTA RICA.  

AT THE SURFACE...A 1001 MB SURFACE LOW ASSOCIATED WITH THE DEEP 
LAYERED LOW OVER CALIFORNIA WAS CENTERED NEAR 37.5N116.5W WITH A 
FRONTAL TROUGH EXTENDING S ACROSS SRN CALIFORNIA AND EXTREME NRN 
BAJA. STRONG WINDS COVERED MUCH OF THE MARINE AREA TO THE W AND 
SW OF THIS LOW...WITH GALES OFF THE CENTRAL CALIFORNIA COAST 
EXTENDING S OF NEAR 33N WITH 25-30 KT NWLY WINDS THEN EXTENDING 
TO NEAR 30N.  A 1033 MB SURFACE HIGH WAS ACROSS THE EPAC NEAR 
35N146W HELPING TO MAINTAIN A TIGHT PRESSURE GRADIENT BETWEEN IT 
AND THE CALIFORNIA LOW...WHILE ALSO PRODUCING A TIGHT GRADIENT 
TO ITS S AND SE TO THE N OF THE ITCZ. FRESH TO STRONG WINDS WERE 
OCCURRING FROM OFFSHORE OF CALIFORNIA S TO ALONG THE W COAST OF 
BAJA AND THEN CURVED ANTICYCLONICALLY ACROSS THE EPAC N OF 22N 
AND W OF 115W TO PRODUCE A BROAD ZONE OF 20-25 KT NE TRADES 
ACROSS THE REGION S OF 30N TO NEAR THE ITCZ AND W OF 125. SEAS 
ACROSS THIS LARGE AREA WERE RUNNING 9 TO 14 FT IN A CONFUSED MIX 
OF NW...SW...AND NE SWELL. 

BOTH THE SURFACE HIGH AND LOW ARE NOT EXPECTED TO MOVE MUCH IN 
THE NEXT 24 HOURS BUT WILL BOTH WEAKEN...WHICH WILL HELP TO 
DIMINISH IN SIZE THE AREAL COVERAGE OF THESE 20-25 KT NELY 
TRADES...WITH SEAS SUBSIDING VERY SLIGHTLY.

$$
STRIPLING