000
AXPZ20 KNHC 041603
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED JUL 04 2007

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 
1545 UTC.

...TROPICAL WAVES...

TROPICAL WAVE ALONG 102W/103W N OF 4N MOVING W 15 KT. SLIGHT 
CURVATURE IS NOTED IN THE LOW-LEVEL WIND FIELD WITH A FEW 
CONVECTIVE CLUSTERS MAINLY W OF THE AXIS. WIDELY SCATTERED 
MODERATE CONVECTION FROM 8N-15N BETWEEN 103W-107W.

TROPICAL WAVE ALONG 115W S OF 18N MOVING W 10-15 KT. NORTHERLY 
FLOW MOVING AROUND THE SUBTROPICAL RIDGE AXIS IS SUPPRESSING ANY 
OBVIOUS CIRCULATION ASSOCIATED WITH THE WAVE...AND ALL 
CONVECTION APPEARS TO BE TIED MORE STRONGLY TO THE ITCZ.

TROPICAL WAVE ALONG 124W/125W S OF 20N MOVING W 10-15 KT. THIS 
WAVE HAS A FAIRLY STRONG AMPLITUDE WITH THE ITCZ PERTURBED AS 
FAR N AS ABOUT 14N. A WEAK LOW-LEVEL CIRCULATION IS EMBEDDED 
ALONG THE WAVE AXIS NEAR 13N124W WITH DEEP CONVECTION PRIMARILY 
ALIGNED NE/SW ALONG THE ITCZ.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 7N77W 8N116W 12N124W 7N140W. 
SCATTERED MODERATE CONVECTION FROM 5N-8N BETWEEN 78W-81W. 
SCATTERED MODERATE WITHIN 120 NM OF AXIS BETWEEN 
88W-97W...102W-107W...AND 124W-129W.

...DISCUSSION...

E OF 110W...
A STRONG UPPER LEVEL ANTICYCLONE CENTERED JUST OFF THE MEXICAN 
COAST NEAR 20N110W AND AN UPPER LEVEL LOW OVER THE NW CARIBBEAN 
JUST E OF THE YUCATAN PENINSULA HAVE JOINED FORCES TO DRIVE A 
STEADY NLY FLOW ALOFT ACROSS MEXICO AND CENTRAL AMERICA E OF 
100W. THIS STRONG NLY FLOW IS PRODUCING VERTICAL SHEAR OVER THE 
AREA AND IS CAUSING THE CONVECTION TO BE QUITE DISORGANIZED...AS 
WELL AS PUSHING IT S AWAY FROM THE MEXICAN COAST. S OF THE 
ITCZ...A BROAD CYCLONIC SHEAR AXIS EXTENDS FROM THE GALAPAGOS 
ISLANDS NW TO 14N110W WITH BROAD-SCALE DRY AIR S OF 6N.

W OF 110W...
A LARGE UPPER LEVEL LOW IS LOCATED W OF THE BAJA PENINSULA NEAR 
27N124W AND IS MOVING SLOWLY W...DRAWING DEEP TROPICAL MOISTURE 
NEWD ACROSS MUCH OF BAJA AND EXTREME NW MEXICO. DUE TO THE 
STRENGTH OF THE SUBTROPICAL RIDGE...HOWEVER...THERE IS NO 
ACCOMPANYING LOW-LEVEL MOISTURE SURGE FROM THE S WHICH HAS 
LIMITED PRECIPITATION OVER THE AREA. ABUNDANT DRY AIR AND 
SUBSIDENCE DOMINATES THE REGION W OF 120W WITH RELATIVELY WEAK 
UPPER FLOW AND LITTLE IN THE WAY OF SIGNIFICANT WEATHER.

$$
BERG