000 WTNT42 KNHC 181436 TCDAT2 TROPICAL STORM BRET DISCUSSION NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL AL022011 1100 AM EDT MON JUL 18 2011 THE CLOUD PATTERN OF THE STORM HAS NOT CHANGED APPRECIABLY IN ORGANIZATION THIS MORNING. THE MAIN BANDING FEATURES ARE WELL REMOVED FROM THE CENTER OVER THE NORTHEAST QUADRANT...AND A SOMEWHAT RAGGED-LOOKING CDO TYPE FEATURE IS EVIDENT. UPPER-LEVEL OUTFLOW CONTINUES TO BE SUPPRESSED OVER THE NORTHWESTERN PART OF THE CIRCULATION. DVORAK INTENSITY ESTIMATES ARE 35 KT AND 45 KT FROM TAFB AND SAB RESPECTIVELY...AND THE CURRENT INTENSITY ESTIMATE IS HELD AT 45 KT. ANOTHER AIR FORCE HURRICANE HUNTER MISSION IS SCHEDULED TO INVESTIGATE BRET THIS AFTERNOON. THE ATMOSPHERIC ENVIRONMENT SHOULD BE MARGINALLY CONDUCIVE FOR STRENGTHENING TODAY AND TONIGHT...WITH DRY AIR AND MODERATE VERTICAL SHEAR AS MITIGATING FACTORS. SOME INTENSIFICATION IS FORECAST WITHIN THE NEXT DAY OR SO...BUT AFTERWARDS INCREASING SHEAR IS LIKELY TO CAUSE A WEAKENING TREND. THE OFFICIAL INTENSITY FORECAST IS SIMILAR TO THE CONSENSUS OF THE INTENSITY GUIDANCE...AND TO THE PREVIOUS NHC FORECAST. BASED ON THE LATEST FIXES...THE CENTER APPEARS TO BE MOVING SLOWLY NORTH-NORTHEASTWARD OR 030/4. THE TRACK FORECAST REASONING IS ESSENTIALLY UNCHANGED FROM THE PREVIOUS ADVISORY PACKAGE. A BUILDING MID-LEVEL RIDGE TO THE SOUTHEAST OF BRET ALONG WITH A BROAD TROUGH OFF THE NORTHEAST U.S. COAST SHOULD CAUSE A NORTH-NORTHEASTWARD TO NORTHEASTWARD MOTION WITH A GRADUAL INCREASE IN FORWARD SPEED OVER THE NEXT SEVERAL DAYS. LATER IN THE FORECAST PERIOD...A TURN TO THE EAST-NORTHEAST WITH SOME ADDITIONAL ACCELERATION IS FORECAST AS THE CYCLONE BECOMES MORE EMBEDDED IN THE HIGHER LATITUDE WESTERLIES. THE OFFICIAL TRACK FORECAST IS AN UPDATE OF THE PREVIOUS ONE. FORECAST POSITIONS AND MAX WINDS INIT 18/1500Z 27.7N 77.3W 45 KT 50 MPH 12H 19/0000Z 28.2N 77.0W 50 KT 60 MPH 24H 19/1200Z 29.2N 76.4W 55 KT 65 MPH 36H 20/0000Z 30.2N 75.7W 55 KT 65 MPH 48H 20/1200Z 31.4N 74.0W 50 KT 60 MPH 72H 21/1200Z 33.5N 70.0W 45 KT 50 MPH 96H 22/1200Z 36.0N 64.5W 35 KT 40 MPH 120H 23/1200Z 38.5N 58.5W 30 KT 35 MPH $$ FORECASTER PASCH 000 WTNT42 KNHC 181436 TCDAT2 TROPICAL STORM BRET DISCUSSION NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL AL022011 1100 AM EDT MON JUL 18 2011 THE CLOUD PATTERN OF THE STORM HAS NOT CHANGED APPRECIABLY IN ORGANIZATION THIS MORNING. THE MAIN BANDING FEATURES ARE WELL REMOVED FROM THE CENTER OVER THE NORTHEAST QUADRANT...AND A SOMEWHAT RAGGED-LOOKING CDO TYPE FEATURE IS EVIDENT. UPPER-LEVEL OUTFLOW CONTINUES TO BE SUPPRESSED OVER THE NORTHWESTERN PART OF THE CIRCULATION. DVORAK INTENSITY ESTIMATES ARE 35 KT AND 45 KT FROM TAFB AND SAB RESPECTIVELY...AND THE CURRENT INTENSITY ESTIMATE IS HELD AT 45 KT. ANOTHER AIR FORCE HURRICANE HUNTER MISSION IS SCHEDULED TO INVESTIGATE BRET THIS AFTERNOON. THE ATMOSPHERIC ENVIRONMENT SHOULD BE MARGINALLY CONDUCIVE FOR STRENGTHENING TODAY AND TONIGHT...WITH DRY AIR AND MODERATE VERTICAL SHEAR AS MITIGATING FACTORS. SOME INTENSIFICATION IS FORECAST WITHIN THE NEXT DAY OR SO...BUT AFTERWARDS INCREASING SHEAR IS LIKELY TO CAUSE A WEAKENING TREND. THE OFFICIAL INTENSITY FORECAST IS SIMILAR TO THE CONSENSUS OF THE INTENSITY GUIDANCE...AND TO THE PREVIOUS NHC FORECAST. BASED ON THE LATEST FIXES...THE CENTER APPEARS TO BE MOVING SLOWLY NORTH-NORTHEASTWARD OR 030/4. THE TRACK FORECAST REASONING IS ESSENTIALLY UNCHANGED FROM THE PREVIOUS ADVISORY PACKAGE. A BUILDING MID-LEVEL RIDGE TO THE SOUTHEAST OF BRET ALONG WITH A BROAD TROUGH OFF THE NORTHEAST U.S. COAST SHOULD CAUSE A NORTH-NORTHEASTWARD TO NORTHEASTWARD MOTION WITH A GRADUAL INCREASE IN FORWARD SPEED OVER THE NEXT SEVERAL DAYS. LATER IN THE FORECAST PERIOD...A TURN TO THE EAST-NORTHEAST WITH SOME ADDITIONAL ACCELERATION IS FORECAST AS THE CYCLONE BECOMES MORE EMBEDDED IN THE HIGHER LATITUDE WESTERLIES. THE OFFICIAL TRACK FORECAST IS AN UPDATE OF THE PREVIOUS ONE. FORECAST POSITIONS AND MAX WINDS INIT 18/1500Z 27.7N 77.3W 45 KT 50 MPH 12H 19/0000Z 28.2N 77.0W 50 KT 60 MPH 24H 19/1200Z 29.2N 76.4W 55 KT 65 MPH 36H 20/0000Z 30.2N 75.7W 55 KT 65 MPH 48H 20/1200Z 31.4N 74.0W 50 KT 60 MPH 72H 21/1200Z 33.5N 70.0W 45 KT 50 MPH 96H 22/1200Z 36.0N 64.5W 35 KT 40 MPH 120H 23/1200Z 38.5N 58.5W 30 KT 35 MPH $$ FORECASTER PASCH