| The rainfall threat from Otto has increased. Isolated amounts of 15 to 20 inches forecast now. Could potentially survive across Central America into the East Pacific. TROPICAL STORM OTTO ADVISORY NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL AL162016 1000 AM EST TUE NOV 22 2016 ...HURRICANE WATCH ISSUED FOR COSTA RICA AND SOUTHERN NICARAGUA... SUMMARY OF 1000 AM EST...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...10.4N 79.2W ABOUT 330 MI...530 KM ESE OF BLUEFIELDS NICARAGUA ABOUT 260 MI...420 KM E OF LIMON COSTA RICA MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H PRESENT MOVEMENT...STATIONARY MINIMUM CENTRAL PRESSURE...986 MB...29.12 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: The governments of Nicaragua and Costa Rica have issued a Hurricane Watch from the Costa Rica/Panama border to south of Bluefields Nicaragua. The weather service of Panama has issued a Tropical Storm Warning for Panama from Nargana to Colon and a Tropical Storm Watch from west of Colon to the Costa Rica/Panama border. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Hurricane Watch is in effect for... * Costa Rica/Panama border to south of Bluefields A Tropical Storm Warning is in effect for... * Nargana to Colon A Tropical Storm Watch is in effect for... * San Andres * West of Colon to the Costa Rica/Panama border A Hurricane Watch means that hurricane conditions are possible within the watch area. A watch is typically issued 48 hours before the anticipated first occurrence of tropical-storm-force winds, conditions that make outside preparations difficult or dangerous. A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area, in this case during the day today. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. Interests elsewhere in Nicaragua, Costa Rica, and Providencia Island should monitor the progress of Otto. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND 48-HOUR OUTLOOK ------------------------------ At 1000 AM EST (1500 UTC), the center of Tropical Storm Otto was located near latitude 10.4 North, longitude 79.2 West. Otto is stationary and a westward drift is expected to begin later today, followed by a faster westward motion on Wednesday. On the forecast track, Otto should be approaching the coasts of Nicaragua and Costa Rica on Thursday. Maximum sustained winds are near 70 mph (110 km/h) with higher gusts. Otto is expected to become a hurricane later today or tonight, with additional strengthening forecast through Thursday. Tropical-storm-force winds extend outward up to 70 miles (110 km) from the center. The estimated minimum central pressure is 986 mb (29.12 inches). HAZARDS AFFECTING LAND ---------------------- RAINFALL: Outer rain bands from Otto are expected to produce rainfall accumulations of 3 to 6 inches over San Andres and Providencia islands, and the higher terrain of central and western Panama and southern Costa Rica through Wednesday. Total rainfall of 6 to 12 inches, with isolated amounts of 15 to 20 inches, can be expected across northern Costa Rica and southern Nicaragua through Thursday. These rains will likely result in life-threatening flash floods and mud slides. WIND: Tropical storm conditions are expected within the warning area today and tonight. Tropical storm conditions are possible within the tropical storm watch area on Wednesday or Wednesday night. Hurricane conditions are possible within the hurricane watch area on Thursday. SURF: Swells generated by Otto are likely to cause life-threatening surf and rip current conditions over the next several days along the coasts of Panama, Costa Rica and Nicaragua. Please consult products from your local weather office. NEXT ADVISORY ------------- Next intermediate advisory at 100 PM EST. Next complete advisory at 400 PM EST. $$ Forecaster Blake TROPICAL STORM OTTO DISCUSSION NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL AL162016 1000 AM EST TUE NOV 22 2016 Otto is close to becoming a hurricane. Satellite images indicate that the cloud pattern has become better organized, with a central dense overcast and broad band feature over the western semicircle evident. The past Air Force Reserve Hurricane Hunter flight recorded maximum flight-level winds of 65 kt, with SFMR winds of about 60 kt. Thus, the initial wind speed is increased to 60 kt for this advisory. Weak-to-moderate southeasterly shear is expected near Otto for the next couple of days while the tropical cyclone moves over warm water. These conditions should allow Otto to continue to strengthen, and almost all of the guidance has Otto as a hurricane before making a central American landfall. The official intensity forecast is raised from the previous one, and lies between the intensity consensus and the HWRF model. Land interaction will cause weakening after landfall, but a stronger Otto is less likely to dissipate as quickly over the eastern Pacific. Most of the guidance now keeps the storm going throughout the period, so the remnant low designation has been changed to a tropical cyclone status over the eastern Pacific. Otto really isn't moving much, with recon fixes showing little net motion during the morning hours. A mid-level ridge is forecast to build over the northwestern Caribbean Sea by tomorrow, which should cause Otto to move slowly westward. As the ridge builds, the forecast speed should increase, especially as the cyclone moves across the eastern Pacific. The guidance continues to trend southward, and the official forecast is shifted in that direction. FORECAST POSITIONS AND MAX WINDS INIT 22/1500Z 10.4N 79.2W 60 KT 70 MPH 12H 23/0000Z 10.4N 79.6W 65 KT 75 MPH 24H 23/1200Z 10.6N 80.6W 70 KT 80 MPH 36H 24/0000Z 10.8N 81.7W 75 KT 85 MPH 48H 24/1200Z 10.8N 82.8W 80 KT 90 MPH 72H 25/1200Z 10.5N 86.5W 45 KT 50 MPH 96H 26/1200Z 10.0N 90.5W 35 KT 40 MPH 120H 27/1200Z 9.5N 94.5W 30 KT 35 MPH $$ Forecaster Blake |