High pressure sticks around as tropical activity continues in the Atlantic

 

A major hurricane continues to churn well off the southeast coast Monday evening as a tropical storm continues to gain strength and is forecast to become a hurricane within the next 24 hours. Hurricane Humberto is a category 4 hurricane with maximum sustained winds of 140 mph. It is currently moving to the north/northwest around 13 mph but will eventually take a turn back to the northeast, moving it further out into the Atlantic by the middle to end of the week.

Tropical Storm Imelda is expected to strengthen, reaching category 1 hurricane strength Tuesday. It is currently off the east coast of Florida with maximum sustained winds of 65 mph and moving north at 9 mph. It, too, will begin to turn back to the northeast Tuesday afternoon - possibly strengthening into a category 2 hurricane Thursday - but not expected to make landfall along the southeast or east coast of the U.S. It will, however, impact Bermuda where Hurricane Watches have been issued as the storm nears by the middle of the week. Tropical storm conditions can be expected beginning Wednesday afternoon with heavy rainfall expected and potential flash flooding conditions. Heavy rain may also occur along the coastal Carolinas which could cause localized flash and urban flooding through Monday night.

High surf and swells from both Humberto and Imelda can be expected, producing dangers rip currents and marine conditions along the east coast over the next few days.

These two Atlantic tropical systems have created sort of a 'back up' in our atmosphere, helping to buckle the jet stream overhead with high pressure building across the Midwest and Great Lakes. Tropical systems are very efficient at releasing a lot of heat into the upper levels of the atmosphere which can cause periods of above average warmth.

Throughout the week the upper-level ridge will eventually begin to break down some, but we really won't see an influx of cooler air. In fact, some of the longer-range outlooks continue to highlight a higher probability for above average temperatures continuing through the middle of the month. A slightly wetter pattern may develop, but right now it looks like the highest chance for any significant rainfall may bypass us to the north. I did introduce just a small chance for precipitation Tuesday, but that at this point is only at 20 percent.