je.st

Home › subtropical

Tag: subtropical

Summary for Subtropical Storm Theta (AT5/AL302020)

2020-11-10 03:59:41| National Hurricane Center (Atlantic)

...SUBTROPICAL STORM FORMS OVER THE OPEN NORTHEAST ATLANTIC... ...RECORD-BREAKING 29TH NAMED STORM OF THE SEASON... As of 3:00 AM GMT Tue Nov 10 the center of Theta was located near 28.8, -40.3 with movement E at 15 mph. The minimum central pressure was 1000 mb with maximum sustained winds of about 50 mph.

Tags: summary storm subtropical subtropical storm

Subtropical Storm Theta Public Advisory Number 1

2020-11-10 03:59:41| National Hurricane Center (Atlantic)

Issued at 300 AM GMT Tue Nov 10 2020 000 WTNT35 KNHC 100259 TCPAT5 BULLETIN Subtropical Storm Theta Advisory Number 1 NWS National Hurricane Center Miami FL AL302020 300 AM GMT Tue Nov 10 2020 ...SUBTROPICAL STORM FORMS OVER THE OPEN NORTHEAST ATLANTIC... ...RECORD-BREAKING 29TH NAMED STORM OF THE SEASON... SUMMARY OF 300 AM GMT...0300 UTC...INFORMATION ---------------------------------------------- LOCATION...28.8N 40.3W ABOUT 995 MI...1600 KM SW OF THE AZORES MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H PRESENT MOVEMENT...E OR 90 DEGREES AT 15 MPH...24 KM/H MINIMUM CENTRAL PRESSURE...1000 MB...29.53 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 300 AM GMT (0300 UTC), the center of Subtropical Storm Theta was located near latitude 28.8 North, longitude 40.3 West. The storm is moving toward the east near 15 mph (24 km/h), and a general east-northeast motion is expected to continue during the next two to three days. Maximum sustained winds are near 50 mph (85 km/h) with higher gusts. Some slight strengthening is possible during the next 12 to 24 hours followed by little change in strength through Thursday. Winds of 40 mph extend outward up to 115 miles (185 km) from the center. The estimated minimum central pressure is 1000 mb (29.53 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 900 AM GMT. $$ Forecaster Papin/Brown

Tags: number public storm advisory

Subtropical Storm Theta Forecast Discussion Number 1

2020-11-10 03:59:41| National Hurricane Center (Atlantic)

Issued at 300 AM GMT Tue Nov 10 2020 000 WTNT45 KNHC 100259 TCDAT5 Subtropical Storm Theta Discussion Number 1 NWS National Hurricane Center Miami FL AL302020 300 AM GMT Tue Nov 10 2020 Over the past 12 h convection has slowly consolidated near the center of a non-tropical area of low pressure over the far northeast Atlantic. Earlier, there was a 2325 UTC ASCAT-B pass that showed that the low-level circulation had become more detached from the warm frontal boundary located to its northeast. In addition, the ASCAT pass showed that winds have increased to near 45 kt on the southeast portion of the circulation near where coldest convective cloud tops were located. Both a 2137 UTC SSMIS and 2324 UTC AMSU microwave pass showed convective banding under the cirrus canopy near where the highest winds were observed. However, water vapor satellite imagery still shows the presence of a broad upper-level low tangled up with the low-level circulation embedded in the convection. Therefore, Theta has been designated as a subtropical storm with maximum wind of 45 kt. Theta has been on a near due east heading over the last 12 h at 90/13 kt. Currently the cyclone is located south of a broad deep-layer longwave trough. This trough is expected to bypass the cyclone to the east and Theta will primarily be steered by southwesterly flow on the northern periphery of a mid-level ridge centered over the Cape Verde islands. This flow will steer Theta slowly to the east-northeast over the next 3-5 days. The track guidance is in good agreement with this solution, with only minor differences in across-track spread. There are somewhat larger differences in the along-track spread related to different forward motion, but the latest NHC track forecast elected to stay close to the track consensus at this time. Thetas structure has evolved from a frontal cyclone to a subtropical cyclone, though a frontal boundary remains nearby on the northeast side of the circulation. This boundary is expected to gradually dissipate and Theta is expected to fully transition to a tropical storm in 24 h as convection erodes the upper-level cyclonic flow overhead. The maximum sustained winds were increased slightly in the first 12 h of the forecast but are kept at 50 kt through 120 h which is on the high end of the intensity guidance. Theta is the 29th named storm in the record-breaking 2020 Atlantic Hurricane Season, breaking the previous record of 28th named storms in 2005. FORECAST POSITIONS AND MAX WINDS INIT 10/0300Z 28.8N 40.3W 45 KT 50 MPH...SUBTROPICAL STORM 12H 10/1200Z 29.0N 38.6W 50 KT 60 MPH...SUBTROPICAL STORM 24H 11/0000Z 29.1N 36.3W 50 KT 60 MPH...TROPICAL STORM 36H 11/1200Z 29.5N 34.3W 50 KT 60 MPH 48H 12/0000Z 30.0N 32.6W 50 KT 60 MPH 60H 12/1200Z 30.5N 30.7W 50 KT 60 MPH 72H 13/0000Z 31.0N 28.7W 50 KT 60 MPH 96H 14/0000Z 32.2N 24.3W 50 KT 60 MPH 120H 15/0000Z 33.3N 20.6W 50 KT 60 MPH $$ Forecaster Papin/Brown

Tags: number discussion storm forecast

Subtropical Storm Alpha Forecast Discussion Number 2

2020-09-18 22:55:47| National Hurricane Center (Atlantic)

Issued at 900 PM GMT Fri Sep 18 2020 000 WTNT44 KNHC 182055 TCDAT4 Subtropical Storm Alpha Discussion Number 2 NWS National Hurricane Center Miami FL AL242020 900 PM GMT Fri Sep 18 2020 Radar data from Portugal indicated that Alpha made landfall at about 1830 UTC with a fairly impressive spiral band signature. It is estimated that the winds were 45 kt at landfall, and a sustained 10-minute wind of 39 kt was recorded at Sao Pedro de Noel. The minimum central pressure is analyzed at 996 mb at landfall due to a 999 mb value at Monte Real with a 31-kt sustained wind. Since these data were recorded, the radar presentation has deteriorated, and satellite imagery suggests the small cyclone could be de-coupling from its mid-level center. The winds are assumed to have come down, with a current estimate of 40 kt. The small cyclone should continue to move northeastward at about 15 kt for the next 12-24 hours before dissipating over northern Spain or the Bay of Biscay. No significant changes are required to the forecast for track or intensity. Additional information on the hazards from this system can be found in products from the Portuguese Institute for Sea and Atmosphere at www.ipma.pt. FORECAST POSITIONS AND MAX WINDS INIT 18/2100Z 40.4N 8.4W 40 KT 45 MPH...INLAND 12H 19/0600Z 42.1N 6.1W 25 KT 30 MPH...POST-TROP/INLAND 24H 19/1800Z...DISSIPATED $$ Forecaster Blake

Tags: number discussion alpha storm