Irma Track Still Remaining A Mystery
Hurricane Irma
5:00 PM EDT on September 02, 2017
Location 18.5 N -44.6 W
Winds: 110 mph Gust: 135 mph
Pressure: 973 mb
Category: 2
Moving: W at 14 mph
Hurricane Irma is now a category 2 after reaching category 3 status 48 hours ago. Irma is still expected to become a major hurricane again over the next several days as it reaches warmer waters. Shear will hinder rapid intensification during the near term though some slow intensification is expected.
The hurricane is forecast to continue to move along the southern portion of the ridge over the central Atlantic. By early next week, it is expected to reach the southwestern portion of that ridge resulting in a more west-northwest motion. Previous forecasts have shown this pattern however the past couple of forecasts show a more southerly track which could pose a threat to the Lesser Antilles by mid-week.
Beyond that time the forecast becomes very complicated. By mid-week a trough is forecast to reside over the eastern half of the CONUS with a strong ridge remaining over the Atlantic. As the week progresses the trough could become cutoff by the ridge to the west.
GFS 500mb Geopotential Height & Anomaly shows the ridge (in red) cutting off the trough (in blue) over the Great Lakes extending down the eastern CONUS.The image shows this potential scenario which will be a major player in the future forecast of Irma. The run above is just one solution among several different solutions that handle the trough and ridge interaction very different resulting in the wide range of possible forecast tracks currently available online. Since the models have difficulty handling fragile situations like this it is hard to pinpoint which solution is the best. This forecast is still one week out and long range forecasts, especially in the tropics, can be unreliable even without this trough uncertainty.
At this point, the forecast could range from landfall from Florida all the way up the east coast or potentially out to sea. If you live in an area that is commonly susceptible to landfalling hurricanes you should begin making plans now in the event this hurricane makes landfall near you.
The bottom line here is that there is a risk that some place on the east coast could be affected by this hurricane but the exact location is unknown as of right now. It may be days before we can narrow down the possible forecast tracks.
I will continue to monitor the situation over the next week and update daily.