000 AXPZ20 KNHC 032122 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Wed Mar 3 2021 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURES... Heavy Rainfall in Western Colombia: Enhanced westerly flow damming up against the Andes Mountains will lead to significant moisture pooling over western Colombia. This combined with a surface trough north of the area and warmer than normal ocean temperatures will lead to periods of locally heavy rainfall over the mountainous terrain through Thursday morning. This rain could lead to isolated flash flooding and mudslides. This region of Colombia is typically one of the wettest as well as the southern one that borders Brazil. Per example, the average rainfall in Quibdo, western Colombia in March is 20.7 inches(526.1 mm). Please refer to local statements issued by your national meteorological agency. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from a 1008 mb low pressure over northern Colombia to 03N85W to 04N98W to 02N100W. The ITCZ continues from 02N100W to 03N120W to 05N135W. A weak trough is within the ITCZ, and extends from 08N135W to 01N139W. Scattered moderate convection is noted within about 60 nm on either side of the ITCZ between 110W and 120W, and from 04N to 06N between the trough axis and 134W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of Tehuantepec: A recent scatterometer pass provided observations of 20 to 25 kt winds across the Tehunatepec region and downwind to near 13N. Fresh to strong N to NE winds will then persist through Thu night. Seas will gradually subside to less than 8 ft by Fri. Another and likely stronger gale-force gap wind event is expected in the Tehuantepec area Sat night through Mon night. A well defined band of clouds, associated with a weakening cold front is reaching Baja California Norte. Fresh to strong W-NW winds and long period NW swell follow the front that extends from a 1008 mb low pressure located N of the area located near 33N120W to 30N118W to 25N120W. In addition, fresh to strong southerly winds are blowing in the northern Gulf of California ahead of the front. Satellite- derived wind data confirmed the presence of these winds, forecast to persist through early Thu morning. As high pressure builds across the region in the wake of the front, expect fresh to locally strong northerly winds across the central and southern Gulf of California Thu night and Fri. These winds will spread beyond the entrance of the Gulf, with fresh to locally strong N-NW winds occurring within about 60 nm of the coast of Mexico between Manzanillo and Cabo Corrientes also Thu night and Fri. Mainly moderate to fresh NW-N winds are expected across the offshore waters of Baja California during the next several days. Seas will build to 8-11 ft in NW swell N of Punta Eugenia by tonight. A second set of NW swell will impact these same waters late Fri through Sun. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Please see Special Features Section above for details on heavy rainfall and flooding potential over western Colombia through Thu morning. Fresh to strong NE to E winds and seas generally in the 6-9 ft range will continue across the Papagayo region through Mon night. Moderate to fresh N to NE winds will continue across the Gulf of Panama and extend southward to 04.5N. These winds are forecast to increase to fresh to strong Sat night through Sun night, with seas building to 8 ft near 80W. Light to gentle variable winds with seas in the 3-5 ft range will dominate elsewhere through the week. No significant swell event is forecast during the next several days. REMAINDER OF THE AREA... Long period NW swell continues to propagate across the northern forecast waters in the wake of the aforementioned cold front that is reaching northern Baja California. By early Fri, seas of 8 ft or greater will dominate most of the forecast waters N of 5N and W of 112W. A new cold front will reach 30N140W on Thu, followed by another round of large NW swell. The front will extend from 30N132W to 26N140W on Fri. Seas will peak 16-17 ft over the NW corner of the forecast area Thu night into Fri morning. This swell event will also propagate through most of the basin N of 05N and west of 110W through Sat. Of note, during March and April of each year, a double ITCZ is present in the southern hemisphere of the eastern Pacific basin, especially during La Nina events when the cold equatorial sea surface temperature are stronger. Currently, the GFS model suggests a second ITCZ south of the equator and W of 120W. $$ GR