000 AXNT20 KNHC 031049 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Mon Oct 3 2022 Tropical Weather Discussion for North America, Central America Gulf of Mexico, Caribbean Sea, northern sections of South America, and Atlantic Ocean to the African coast from the Equator to 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0600 UTC surface analysis and satellite imagery through 1030 UTC. ...SPECIAL FEATURES... A far eastern Atlantic tropical wave embedded within an elongated area of low pressure has its axis near 32W from 03N to 15N. It is moving westward at about 5 kt. Disorganized scattered moderate convection is occurring from 05N to 14N between 28W-35W. Environmental conditions are forecast to be favorable for some gradual development, and a tropical depression is likely to form around the middle part of this week. Further development will become less likely by the end of the week due to increasing upper- level winds. The system is forecast to move westward, then turn northwestward or northward by the end of the week over the eastern tropical Atlantic. This system has a medium chance of becoming a tropical cyclone during the next 48 hours. Please refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details. ...TROPICAL WAVES... A broad mid-Atlantic tropical wave has its axis near 51W from 04N to 17N, moving westward at 10-15 kt. Scattered moderate to isolated strong convection is within 120 nm west of the wave from 08N to 11N and from 14n to 17N. Similar convection is east of the wave from 11N to 14N between the wave and 45W. Further development of the wave is possible, however, and a tropical depression could form during the next few days while it moves generally westward at 15 to 20 mph, reaching the Windward Islands and the eastern Caribbean Sea by midweek. This system has a low chance of tropical cyclone development through the next 48 hours, and a medium chance through 5 days. For the latest formation chances on this tropical wave, please read the Tropical Weather Outlook at hurricanes.gov. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic along the coast near the Senegal-Gambia border near 10N27W and continues southwestward to 10N26W and to 07N35W, where overnight scatterometer data indicates that it transitions to the ITCZ and continues to east of a tropical wave near 10N48W. It resumes west of the tropical wave to near 10N60W. In addition to convection associated to the tropical waves mentioned above, scattered moderate to isolated strong convection is within 180 nm north of the trough between 24W-28W, and within 120 nm north of the of the ITCZ between 35W-38W and within 60 nm northeast of the trough between 44W-48W. Numerous moderate convection is within 120 nm south of the ITCZ between 35W-38W, and also near the Guinea Bissau- Guinea coast. ...GULF OF MEXICO... A surface trough extends from the southwestern Gulf near 22N97W east-southeast to across the northern Yucatan Peninsula and continues to a 1010 mb low in the western Caribbean Sea near 15N82W. Isolated showers are possible near the trough. Another surface trough is over the NE Gulf near 29N and east of 90W. No convection is noted with this trough. Moderate northeast winds are behind it. Otherwise, high pressure stretching southward from the upper Great Lakes to the Gulf is maintaining dry and stable conditions throughout the Gulf, with the associated gradient allowing for gentle to moderate north to northeast winds and relatively low seas of 2-4 ft per buoy observations and an altimeter pass that detected the seas over the far eastern Gulf. For the forecast, the trough over the NE Gulf will sink to near 27N east of 90W today, while at the same time, high pressure from the central U.S. continues to build southward over the region. A frontal trough currently over the southeastern U.S. will transition into a cold front and move southward across the eastern Gulf tonight through Tue night, followed by another area of relatively weak high pressure. This will allow for moderate to fresh northeast to east winds to occur mainly over the NE Gulf. These winds then become east gentle to moderate on Wed, with little change expected through Fri night. Moderate to fresh northeast to east winds will develop over the southeastern Gulf starting Fri as a tight gradient builds behind a cold front that will reach the vicinity of South Florida and the Keys. ...CARIBBEAN SEA... A surface trough is analyzed from the southwestern Gulf of Mexico east-southeastward to across the northern Yucatan Peninsula and to a 1010 mb low just east of the Honduras-Nicaragua border, and from there to just offshore of southern Nicaragua. Clusters of scattered showers and thunderstorms are seen from 13N to 15N between 78W-and the coast of the Honduras-Nicaragua border. An overnight ASCAT pass depicted fresh northwest to north winds west of the low and the tough segment that extends south of the low. Scattered showers and isolated thunderstorms are noted from near the Windward Passage southwestward to eastern Jamaica and to near 15N78W. Similar activity is over and adjacent the some sections of the Lesser Antilles, and over the south-central waters from 12N to 15N between 73W-76W. Locally moderate to fresh winds and higher seas are in and near the heaviest of the showers and thunderstorms. Otherwise, light to gentle winds along with relatively low seas of 1-3 ft are present over the western part of the basin, while gentle to moderate east to southeast trade wind and seas of 3-5 ft remain over the rest of the basin. For the forecast, the aforementioned surface trough is forecast to persist in the general area through at least Wed. A tropical wave currently east of the forecast Tropical N Atlantic waters has its axis near 51W. Scattered showers and thunderstorms are increasing with this wave. Further development of the wave is possible, however, and a tropical depression could form during the next few days while it moves generally westward, reaching the Windward Islands and the eastern Caribbean Sea by midweek. Elsewhere, gentle to moderate trades and slight to moderate seas are expected across the basin over the next few days. ...ATLANTIC OCEAN... A cold front extends southwestward from a 1009 mb low off the Mid-Atlantic coast south-southwest through 31N71W to 28N74W, where it continues as a stationary front across the NW Bahamas and to near 24N80W. Scattered showers and isolated thunderstorms are within 60-90 nm east-southeast of the cold and stationary fronts. Scattered showers and thunderstorms are east of this activity from 22N to 31N between 61W-69W due to upper dynamics provided by an upper-level trough that extends from 31N72W to 25N69W and to near 21N67W. Another upper-level trough runs northward from east of the Leeward Islands at 15N55W to an upper-level low near 23N55W. At the surface, a trough is analyzed from just east of Barbados to 18N59W. Scattered showers and thunderstorms are along and within 60 nm of this trough. Numerous showers and thunderstorms are increasing within 120 nm of the low in the S semicircle. Scattered showers and thunderstorms are within 120 nm of the low in the N semicircle. In the east Atlantic, a nearly stationary upper-level low is seen on water vapor imagery to be near 30N31W. Broad upper troughing with this feature is noted from 20N to 35N and between 20W-40W. At the surface, a trough extends from 31N29W to 27N30W and to 23N36W. Another trough is analyzed from 31N34W to 28N39W. Scattered showers and thunderstorms, mainly attributed to the upper-level low, are from 28N to 33N between 27W-32W. Isolated showers are possible along and near the surface troughs. A cold front dropping southward extends from 31N36W to 31N40W and northwestward to 32N43W, where it becomes stationary to 34N48W. No convection is seen with this front as it is surrounded by a pretty stable air mass. Please refer to the Special Features and Tropical Waves and Monsoon Trough/ITCZ sections for additional weather in the Atlantic Basin. The 1021 mb Bermuda High near 31N51W is supporting light to gentle winds and seas of about 2-4 ft north of 20N between 30W-60W. An overnight altimeter pass helped confirm these seas. To the west, mainly gentle to moderate southerly winds along with seas of 4-6 ft are north of 20N between 60W and the Georgia- Florida coast. Near the Canary Islands, light to gentle winds and seas of 4-6 ft due to a northerly swell exist north of 20N between the northwest coast of Africa and 30W. Farther south, gentle to moderate northeast to east trade wind and seas of 5 to 8 ft are evident from 10N to 20N between central African coast and the Lesser Antilles. Gentle to moderate monsoonal and southerly winds along with seas of 4-7 ft seas due to a southerly swell prevail for the rest of the Atlantic Basin. For the forecast west of 55W, the aforementioned cold front will reach from near 31N68W to 27N73W and to eastern Cuba by late tonight as a stronger cold front moves into the northwest part of the area from near 31N76W to near Melbourne, Florida. The second front will merge with the first front late Tue night. The merged front will reach from near 31N66W to 27N69W and to 24N71W, where it will weaken to eastern Cuba by late Wed night. Fresh northerly winds will follow the second front and merged front through late Wed night. The merged front will stall reach from near 31N64W to 26N68W, to the central Bahamas and to the vicinity of South Florida and the Keys late Thu. Fresh northeast winds will begin to develop in the southwest part of the area, including the Straits of Florida, as the pressure gradient tightens behind the stationary frontal boundary. These conditions are expected to last into Fri night. $$ Aguirre