Classic Hand Analysis of Hurricane Hermine Just Prior to Landfall! (credit: NWS Little Rock, Arkansas)
DISCUSSION: Just a little over an hour ago (i.e., in the vicinity of 10:00 PM CDT), Hurricane Hermine was positioned just to the south of Saint Marks, Florida (located in the eastern part of the Florida Panhandle). One of the neater features associated with the circulation of Hermine is the particularly tight pressure gradient which is evident in the hand-drawn analysis attached above (courtesy of forecasters at the National Weather Service office located in Little Rock, Arkansas). This notably strong pressure gradient is especially noticeable from the center of Hermine and outwards both towards the northwest, southwest, and southeast. As far as a meteorologically-based explanation, the best reason for why there was an anomaly located just northwest of the core of this tropical cyclone at that point in time was the possible movement of drier air from the mid-levels towards the surface within the core of the circulation of Hermine. As a consequence, this naturally led to an inconsistency in the magnitude of the pressure gradient in the vicinity of the northeast quadrant of Hermine's circulation center as noted in the hand-drawn analysis above.
In addition, you will note now on the east and north easterly side of the circulation associated with a currently weakening Hurricane Hermine, there is a plethora of deep tropical moisture flowing around the eastern half of the tropical storm based on widespread dew point values in excess of 70°F. This is a classic feature often found with intensifying tropical cyclones based on their ability to transport large quantities of moisture towards the center as it wraps around the center of the circulation both over the ocean and onshore during the post-landfall phase. You can also denote the classic cyclonic flow occurring within the larger-scale wind field as denoted by the southwesterly-to-southeasterly flow (from south-to-north) occurring within the eastern half of this tropical storm and the northeasterly-to-northwesterly flow (north-to-south) occurring within the western half of this weakening tropical storm!
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©2016 Meteorologist Jordan Rabinowitz