Things are getting very interesting in the weather world these days. With our drought peaking in intensity once again, the need for rain is greater than ever, especially across northeast Oklahoma. Meanwhile, the Tropics have grown active with two named storms, one of which may have a large impact on the United States next week.
Starting with our current drought situation, Oklahoma has seen improvement in southern regions while "Exceptional" drought has grown even more widespread further north. The improvement came from the soaking 2-4" of rain that fell last weekend in southeast Oklahoma. Much of that rain missed northeastern portions of the state so drought conditions only grew worse. After driving on I-44 northeast of Tulsa, it was easy for me to pick out many ponds that have nearly gone dry.
A series of upper-level waves with an adjoining cold front at the surface will be a significant blessing in light of our dire drought situation. Starting Friday, slow-moving areas of rain and thunderstorms will progress into eastern Oklahoma. The axis of rain will shift further east over the weekend, putting Green Country near the bullseye of this soaking system. The attached map above shows the projected rainfall through Tuesday morning, according to the Hydrometeorological Prediction Center. I think 1-3" of rain will likely fall before the system shifts slowly east by Monday. Unfortunately, this means some weekend plans may be very soggy. The chance of severe weather is very low given weaker instability and dynamics, but the coverage of rain will likely be great. These periods of rain mean cooler temperatures as well. Those readings will go back up again as another ridge of high pressure builds in behind the incoming upper-level waves.
Finally, we have an active pattern in the Tropics. We are less than a month away from the peak of hurricane season so Tropical Storms Isaac and Joyce are right on schedule. Joyce will be a non-issue for the U.S. as it will likely be steered well out into the Atlantic Ocean closer to Bermuda. It's a different scenario for Isaac, which is currently centered south of Puerto Rico. It's forecast track becomes rather uncertain after the next couple of days when it passes by the island of Hispañola and Cuba. If we split the difference from all of the computer model tracks, Isaac would head into the eastern Gulf of Mexico, brushing by the west coast of the Florida peninsula before heading inland further north. That would still bring Isaac uncomfortably close to Tampa, the location of the GOP Convention next week. Some computer models even bring Isaac into the central Gulf of Mexico south of Louisiana. Needless to say, Isaac's track will have many implications and will be a growing story into early next week.