Summer ends tomorrow (Friday, August 31st) and it’s one we’ll remember with because of unusual heat, very little rainfall and a dramatic cooling in the final three weeks that led August to end near normal in temperatures…so why not start autumn 2012 on a stormy and cooler note? Remember what I have said here many times, “Extremes beget extremes”.
I know you have been keeping up with the news on Hurricane Isaac over the past few days, but Isaac’s story won’t end down at the Gulf Coast. Like many landfalling tropical cyclones, its impacts will be felt for many days afterward (not counting the damage which will take months or longer to clean up and repair). The remnants of Isaac are on the move today, slowly for now but steadily heading toward Arkansas. From there the storm will cross Missouri and then make a right turn near St. Louis on Friday before taking an eastward course just north of the Ohio River on Saturday and Sunday.
On that path we will see a once powerful and destructive storm turn into good news for many people and communities as soaking rainfall hits areas dealing with extreme drought from the Mid South into the Midwest. The rains will either end or greatly reduce the drought by next week, and beyond that there may be an active weather pattern featuring more storms and rounds of cooler air through mid September. It may be too late for many farmers and gardeners, but it’s always a relief to see the rains return after the seemingly unending intense sunshine, heat and dust that started back in late April and rapidly expanded into a major drought by June and July.
One thing that some readers may find surprising is that we need a number of tropical storms to hit the United States each year in order to keep drought at bay. We have had a dearth of landfalling storms in the past five years, and it has been seven years since a major hurricane (Category 3 or higher) hit our coastline. This year we were grazed by Alberto and Beryl early in the season along the east and southeast coast, with little resulting rainfall. Debby helped relieve drought in Florida in late June, but its impacts were limited to the northern half of Florida and extreme southeast Georgia. In contrast, Isaac will easily be looked back upon as a turning point in the 2012 drought.
Moving forward we need to keep the rain coming every week, but you can count the tropics out for a while. The hurricane season has been a quiet one (many named storms…nearly all weak and short-lived) and although Tropical Storm Kirk is in the central Atlantic Ocean today and Leslie is about to form southeast of Kirk, neither storm is likely to get close to the United States. Beyond the next two weeks there are global pattern changes indicating that the hurricane season may be slowing or shutting down by late September. I wouldn’t be surprised if no other tropical activity approached the Gulf or Atlantic coastlines this year.
Here in the Ohio Valley we’ll likely have the wettest weekend and wettest three-day period for the year from Friday night into Labor Day with 1 to 3 inches of rainfall possible (check out this model forecast). Isolated locations may pick up four inches or more. By late next week a pleasant autumn air mass will settle into the region. Between the rain and the cooler air (and the steadily diminishing daylight) we’ll be effectively wiping out the regional drought and shutting down the unusual heat for 2012 in the Ohio Valley (no more 90s). Have alternate plans ready if the weekend rainfall prevents you from venturing outdoors…but make sure to enjoy the rain too. We need it and for the first time in a long time, everyone will get wet!
Keep your eyes on the sky and enjoy the changing weather!
Skyeye Weather LLC