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Post-Tropical Cyclone Isaias Advisory Number 33


Issued Active alert

Start Time

Wed 08/05/2020 05:00 AM EDT

End Time

Wed 08/19/2020 05:00 AM EDT



Full Alert Message

BULLETIN Post-Tropical Cyclone Isaias Advisory Number 33 NWS National Hurricane Center Miami FL AL092020 500 AM EDT Wed Aug 05 2020 ...RAIN AND GUSTY WINDS CONTINUE TO SPREAD OVER EASTERN QUEBEC... ...THIS IS THE LAST NHC ADVISORY... SUMMARY OF 500 AM EDT...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...47.5N 71.8W ABOUT 55 MI...90 KM NNW OF QUEBEC CITY MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...NNE OR 15 DEGREES AT 28 MPH...44 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 500 AM EDT (0900 UTC), the center of Post-Tropical Cyclone Isaias was located near latitude 47.5 North, longitude 71.8 West. The post-tropical cyclone is moving toward the north-northeast near 28 mph (44 km/h), and this general motion is expected with a decrease in forward speed through tonight. Maximum sustained winds are near 40 mph (65 km/h) with higher gusts. Weakening is expected, and the winds are expected to drop below tropical-storm force this morning. The post-tropical cyclone is expected to dissipate over southeastern Canada on Thursday. Tropical-storm-force winds extend outward up to 140 miles (220 km) to the northeast and east of the center primarily over and near the St. Lawrence River. The estimated minimum central pressure is 1000 mb (29.53 inches). HAZARDS AFFECTING LAND ---------------------- WIND: Gale-force winds will continue over and near the St. Lawrence River this morning. Gale-force wind gusts are possible elsewhere over southeastern Quebec today. See products issued by Environment Canada for more information. RAINFALL: Rainfall accumulations of 1 to 3 inches are expected along and near the track of Isaias across southern Quebec. Even though the rainfall has ended, scattered minor to moderate and isolated major river flooding is ongoing across portions of the Mid-Atlantic with most rivers expected to fall below flood stage by later today. SURF: Swells generated by Isaias will affect the coast of the Northeast United States through this morning. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- This is the last public advisory issued by the National Hurricane Center on this system. Additional information on the post-tropical cyclone can be found in products issued by the Canadian Hurricane Center at