180 
axpz20 knhc 130304
twdep 
Tropical weather discussion 
NWS National Hurricane Center Miami FL
0405 UTC Mon Feb 13 2012
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 
0230 UTC.
...Intertropical convergence zone/monsoon trough...
The monsoon trough is along 05n77w to 01n90w to 06n111w to 
03n133w. The intertropical convergence zone axis extends from 
03n133w to 02n140w. No significant convection is noted.
...Discussion...
An upper level shortwave trough is swinging E across the NE 
portion of the discussion area with its mean axis extending from 
32n111w to a base at 15n125w. Some upper level moisture precedes 
the trough...and is currently moving E across the southern conus 
between eastern New Mexico and SW Georgia with the moisture also 
extending to the S over the Gulf of Mexico to the N of 27n.
A flattening upper level ridge is over the western portion of 
the area from 32n131w to 14n136w. Some upper level moisture is 
spilling E of the ridging across the waters N of 26n W of 
125w...and also from 13n to 26n W of 135w. An upper level 
anticyclone is to the far E near 10n81w centered just N of 
Panama. Upper level moisture is being advected from the deep 
tropics to the N-NE around the western periphery of this 
anticyclone to across southern Mexico and N Central America. 
Otherwise dry and stable air covers the majority of the 
remainder of the discussion waters.
At the surface...1029 mb high pres is NW of the area near 
31n144w with a ridge axis entering the waters near 30n140w and 
continuing to the se to near 22n111w. A tight pres gradient is 
in place over the W central waters between this ridging and 
lower pres to the S associated with the ITCZ. As a result fresh 
trades are present in the areas from 08n to 22n W of 130w and 
from 10n to 18n between 125w and 130w...as indicated by earlier 
ascat and experimental oscat scatterometer passes. These winds 
will persist through the early part of the week encompassing the 
area from 09n to 22n W of 130w by Tue evening.
An experimental oscat scatterometer pass indicated only 10-15 kt 
winds W of the Baja California peninsula although expect fresh 
winds to return N of 28n E of 120w by Mon evening as the pres 
gradient tightens over the region. A cold front is forecast to 
drop S of 32n late Mon into Tue...reaching from 29n114w to 
28n120w to 29n128w by Tue evening with fresh northerly winds 
behind it.
A weak trough extends from 15n106w to 09n111w. Earlier ascat 
scatterometer data indicated that associated winds are only  
5-15 kt in the vicinity of the trough and all associated deep
convection has also dissipated.
Otherwise...NW swell of 8-11 ft with peak wave periods of 15-17 
seconds covers the waters W of 100w. This swell will reach to 
96w by Mon evening...then will begin to decay to less than 8 ft 
at its eastern extent on Tue.
...Gap winds...
an earlier experimental oscat scatterometer pass sampled 30 kt 
winds in the Gulf of Tehuantepec and observations from land- 
based station ixtepec in Oaxaca Mexico are still gusting to 25 
kt. The Gale Warning will remain in effect through 09z...with 
winds rapidly diminishing to less than 20 kt by Mon afternoon.
Fresh trade winds in the SW Caribbean will continue to funnel 
through the passes of Central America into and downwind of the 
Gulf of papagayo at 20-25 kt through Tue evening. The strongest 
winds will occur during the morning hours with the aide of 
enhanced drainage flow off the the adjacent land areas.
Fresh northerly winds will continue over the western Gulf of 
Panama through Tue evening.
$$
Lewitsky