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axpz20 knhc 280917
twdep
Tropical weather discussion
NWS National Hurricane Center Miami FL
1005 UTC Mon may 28 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 0600 UTC surface analysis and satellite imagery through
0845 UTC.
...Intertropical convergence zone/monsoon trough...
The monsoon trough extends from Colombia near 10n72w to 09n86w
to 12n99w low pres 1008 mb near 09n104w to 08n105w to 07n122w...
where it transitions to ITCZ...continuing on beyond 06n140w.
Scattered moderate to strong convection noted within 180 nm N
and 150 nm S of trough between 104w and 114w.
...Discussion...
The subtropical ridge extends se from 1030 mb high pres near
38n152w through 30n130w to 16n107w. The pres gradient between
this ridge and lower pres over the southern rockies and N
central Mexico is producing fresh to strong NW-N winds offshore
of Baja California N of 24n. This low pres area will shift
eastward over the next day or so...weakening the pres gradient
and the winds off Baja California. Fresh N winds will be
confined to N of 28n by Mon evening through the end of the
period Tue evening.
The aforementioned subtropical high will be forced southward and
weaken as a northern stream system encroaches upon it from the
NW. Fresh trade winds currently lie over much of the area
between the ITCZ and 25n W of 125w. The area of fresh trades
will shrink southwestward through Tue evening in response to the
changes in the subtropical high.
Gentle to moderate winds prevail E of 110w to Central
America...associated with the monsoon trough. A broad area of
low pres is embedded in the monsoon trough along about 104w. Mid
level cyclonic turning can be seen in satellite imagery a few
degrees to the W...along 106w/107w...shifting W 10-15 kt. This
wave like feature will continue to move wwd during the next
24-48 hours...and maintain active convection until it reaches
115w...where drier and more stable atmospheric conditions
prevail. Conditions do not appear favorable for any significant
development of this system over the next two days.
$$
Stripling
