je.st
news
Tropical Depression EIGHT-E Forecast Discussion Number 4
2013-08-04 10:50:10| National Hurricane Center (East Pacific)
Issued at 200 AM PDT SUN AUG 04 2013 000 WTPZ43 KNHC 040849 TCDEP3 TROPICAL DEPRESSION EIGHT-E DISCUSSION NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL EP082013 200 AM PDT SUN AUG 04 2013 THERE HAS BEEN LITTLE CHANGE IN THE OVERALL CONVECTIVE PATTERN SINCE THE PREVIOUS ADVISORY. MODERATE NORTH TO NORTHEASTERLY WIND SHEAR IS KEEPING WHAT LIMITED CONVECTION THERE IS DISPLACED TO THE SOUTH OF THE CENTER...AND A 0542 UTC AMSU OVERPASS REVEALED VERY LITTLE IN THE WAY OF BANDING FEATURES. SATELLITE INTENSITY ESTIMATES ARE 45 KT FROM UW-CIMSS ADT...35 KT FROM TAFB...AND 30 KT FROM SAB. GIVEN THE LACK OF ANY SIGNIFICANT CONVECTIVE BANDING FEATURES...THE INTENSITY IS BEING MAINTAINED AT 30 KT FOR THIS ADVISORY. THE INITIAL MOTION ESTIMATE IS 270/08 KT BASED PRIMARILY ON MICROWAVE SATELLITE FIXES. A WESTWARD MOTION IS FORECAST TO CONTINUE FOR THE NEXT 24 HOURS OR SO...FOLLOWED BY A TURN TO THE WEST-NORTHWEST. THE NHC MODEL GUIDANCE IS IN REASONABLE AGREEMENT ON THIS SHORT-TERM TRACK SCENARIO...BUT THEN DIVERGES SIGNIFICANTLY AFTER THAT DUE TO THE EXPECTED STRENGTH AND VERTICAL DEPTH OF THE CYCLONE. THE ECMWF IS FORECASTING A MUCH WEAKER SYSTEM THAT MOVES MORE WESTWARD AND REMAINS EMBEDDED WITHIN THE ITCZ...WHEREAS THE GFS AND HWRF ARE FORECASTING A STRONGER AND DEEPER STORM THAT MOVES POLEWARD OUT OF THE ITCZ. GIVEN THE CONDUCIVE ENVIRONMENTAL AND OCEANIC CONDITIONS AFTER 18-24 HOURS THAT SHOULD ALLOW THE CYCLONE TO INTENSIFY POSSIBLY TO NEAR HURRICANE STRENGTH...THE OFFICIAL FORECAST LEANS MORE TOWARD THE GFS...GFS-ENSEMBLE...AND HWRF SOLUTIONS...AND LIES NEAR BUT SLIGHTLY TO THE RIGHT OF THE CONSENSUS MODEL TVCE. THE MODERATE NORTHERLY VERTICAL WIND SHEAR THAT HAS BEEN PLAGUING THIS SYSTEM FOR THE PAST FEW DAYS IS FORECAST TO WEAKEN TO LESS THAN 5 KT BY 48 HOURS AS THE CYCLONE MOVES UNDER A RIDGE AXIS THAT LIES ALONG 130W LONGITUDE. SSTS ARE 28C AND WARMER AND THE MIDDLE TROPOSPHERE IS FORECAST TO BE MOIST WITH HUMIDITY VALUES IN EXCESS OF 70 PERCENT. THESE CONDITIONS WOULD FAVOR AT LEAST SOME MODEST STRENGTHENING OVER THE NEXT 3 DAYS UNTIL THE CYCLONE MOVES OVER SUB-26C SSTS BY 96 HOURS. THE BULK OF THE RELIABLE INTENSITY GUIDANCE IS STILL FORECASTING THE DEPRESSION TO BECOME A HURRICANE BY 48 HOURS...WHICH IS NOT OUT OF THE QUESTION GIVEN THAT THE CYCLONE IS EXPECTED TO MAINTAIN A MOIST EQUATORIAL INFLOW PATTERN. THE INTENSITY FORECAST IS SIMILAR TO THE PREVIOUS ADVISORY...AND IS CLOSE TO BUT SLIGHTLY LOWER THAN THE CONSENSUS MODEL ICON. FORECAST POSITIONS AND MAX WINDS INIT 04/0900Z 12.8N 125.6W 30 KT 35 MPH 12H 04/1800Z 12.8N 126.6W 35 KT 40 MPH 24H 05/0600Z 12.8N 128.0W 40 KT 45 MPH 36H 05/1800Z 12.9N 129.5W 45 KT 50 MPH 48H 06/0600Z 13.6N 131.1W 50 KT 60 MPH 72H 07/0600Z 14.9N 134.4W 60 KT 70 MPH 96H 08/0600Z 16.1N 138.2W 50 KT 60 MPH 120H 09/0600Z 17.3N 142.0W 40 KT 45 MPH $$ FORECASTER STEWART
Tags: number
discussion
tropical
depression
Category:Transportation and Logistics
Latest from this category |
All news |
||||||||||||||||||
|
|||||||||||||||||||