AXPZ20 KNHC 210312
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Fri Feb 21 2020
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
Based on 0000 UTC surface analysis and satellite imagery through
Gulf of Tehuantepec Storm Warning: A cold front approaching the
SW Gulf of Mexico will shift SE tonight, ushering in northerly
winds through the Chivela Pass. These winds will spill into the
Gulf of Tehuantepec and rapidly accelerate, reaching gale force
around midnight tonight. Winds are forecast to reach strong gale
through the day Fri, then minimal storm force Fri evening into
the early morning hours of Sat. Winds will then gradually
diminish below gale force by Sun afternoon. Very large seas will
build with these winds, reaching near 22-24 ft by early Sat.
Please read the latest High Seas Forecast issued by the National
Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 or at
website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
A surface trough extends from western Costa Rica near 09N85W to
05N90W to 03N106W. The intertropical convergence zone axis
continues from 03N106W to 07N130W to 05N140W. Scattered
moderate convection is within 10N89W to 10N85W to 07N81W to
02N85W to 02N97W to 08N94W to 10N89W, within 09N126W to 06N123W
to 07N127W, and also within 10N135W to 11N131W to 10N128W to
07N128W to 06N133W to 10N135W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
Please read the Special Features section for more details about
the developing Storm Warning in the Gulf of Tehuantepec.
A broad and weak ridge extends SE across the offshore waters,
with earlier scatterometer data indicating mainly gentle to
light NW-N winds across the waters, while earlier altimeter data
showed mainly 4-6 ft seas in NW-N swell, except 3 ft or less in
the Gulf of California.
The ridge will weaken during the next few days, in advance of
an approaching cold front. The front will be dissipating as it
traverses across Baja California Norte and the northern Gulf of
California by Sat. Winds will manage to increase to moderate to
locally fresh speeds as the gradient tightens in the wake of the
front. Winds may even reach fresh to strong offshore of Cabo
Corrientes by the end of the weekend into early next week. Seas
are forecast to gradually build to 6-9 ft in NW swell behind the
front this weekend.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
Fresh NW swell generated by a strong gap wind event in the Gulf
of Tehuantepec will propagate into the waters offshore of
Guatemala and El Salvador Fri night through Sun. Seas will reach
up to 14-16 ft near 11N96W.
Gulf of Papagayo: Fresh to strong winds will continue to pulse,
strongest during the overnight and early morning hours, through
the upcoming weekend. These winds will weaken early next week as
the local pressure gradient weakens. Seas will reach between
8-11 ft during this time period.
Gulf of Panama: Fresh to strong northerly winds will pulse
through the upcoming weekend, diminishing some early next week.
Seas will build to up to 6-8 ft at times with these winds.
Elsewhere, mainly gentle to moderate winds, and seas of 4-6 ft
will prevail into early next week.
Looking ahead, an unseasonably strong southerly jet is forecast
to develop along the lee of the Andes over eastern Ecuador/SW
Colombia late Sat into early Sun. During this period, the
environmental conditions appear favorable for convection to
develop. Locally heavy rainfall may be possible due to strong
REMAINDER OF THE AREA...
A cold front is analyzed from 30N129W to 25N140W, with fresh
northerly fresh winds behind the front noted by earlier
scatterometer passes. NW swell is arriving behind the front as
well, with earlier altimeter data showing seas of 8-10 ft. The
front will gradually weaken as it shifts E-SE across the northern
waters through the end of the week, while the associated NW
swell gradually decays as well.
Fresh NE-E swells generated by gap wind events in the Gulf of
Tehuantepec and Gulf of Papagayo will propagate into the waters
from the equator to near 13N, between 90W and 115W beginning
this weekend, gradually decaying early next week.
Elsewhere, mainly moderate to fresh trades are noted over the
W-central waters to the N of the ITCZ, along with seas of 5-8 ft.
Trades are forecast to strengthen to fresh to strong across and
expanding area Fri through early next week as strong high pres
builds from NW-SE across the area in the wake of the above
mentioned cold front.