Flhurricane.com - Central Florida Hurricane Center - Tracking Storms since 1995Hurricanes Without the Hype! Since 1995
The Atlantic is quiet
|
Show Selection: |
| #888300 (Received by flhurricane at: 4:44 AM 21.Apr.2017) TCDAT1 Tropical Storm Arlene Discussion Number 8 NWS National Hurricane Center Miami FL AL012017 500 AM AST Fri Apr 21 2017 Arlene has maintained a small area of deep convection surrounding the center of the cyclone, with some of the cloud tops as cold as -50 deg C. However, satellite trends over the past couple of hours indicate that the areal coverage of the convection has decreased significantly since the 0600 UTC satellite intensity estimates, an indication that Arlene is beginning to lose its tropical characteristics as the cyclone interacts with a frontal zone and also moves over cooler water. Dvorak current intensity estimates remain at 45 kt, and that is the intensity used for this advisory. The initial motion estimate is now 270/27 kt. Arlene has accelerated westward during the past 6 hours as the cyclone moves around the northern periphery of a larger deep-layer extratropical low that has remained nearly stationary near 36N 48W. The small cyclone or its remnants are expected to move in a cyclonic loop around this low for the next couple of days. Arlene is gradually running out of space within the narrow warm sector of the aforementioned occluded low pressure system, and merger with one or more frontal zones is likely during the next 12 hours. The new official intensity forecast continues the trend of the previous advisory, which shows Arlene degenerating to a post-tropical cyclone by 12 hours, and dissipating by 24 hours when the system is expected to be absorbed into the larger baroclinic low. Tropical storms in April are rare and Arlene is only the second one observed in this month during the satellite era. It should be noted, however, that this type of storm was practically impossible to detect prior to the weather satellite era. FORECAST POSITIONS AND MAX WINDS INIT 21/0900Z 40.0N 48.0W 45 KT 50 MPH 12H 21/1800Z 39.5N 50.4W 40 KT 45 MPH...POST-TROPICAL 24H 22/0600Z...DISSIPATED $$ Forecaster Stewart |
