Just as extreme drought expanded through more of Garrett and southwest Allegany County late last week, Mother Nature is providing needed rain to conclude September.
Helene combined with an upper low that is swirling across the central Appalachians through Tuesday. Rainfall begin Sunday night and will continue through Tuesday evening.
The rainfall intensity will be light to briefly heavy with rain amounts of around 1 inch, locally up to 3 inches along the eastern-facing ridges of Garrett, Grant and Pendleton County.
A few valley spots adjacent to these eastern ridges will see poor drainage and possibly small stream and creek flooding. Remember, when you approach a flooded roadway, turn around because the water is usually deeper than what it appears. Another hazard to beware of will be dense fog on the eastern slopes of the mountains, particularly after dark and before sunrise through Wednesday.
Since the start of summer, rainfall deficits range from 7 inches in southern Garrett County to northwestern Grant County to 3.30 inches for the remainder of Western Maryland and the Potomac Highlands in West Virginia. The early week rainfall will likely reduce these deficits to 1.50 to 4 inches.
The Drought Monitor reviews rainfall from Tuesday at 8 a.m. of the previous week to Tuesday at 8 a.m. the following week to assess changes in drought status. Given the recent soggy trends, expect at least two categorical improvements when the next update occurs on Thursday. Instead of severe to extreme drought (level 2 to 3 drought), Western Maryland and the Potomac Highlands will likely be downgraded to a moderate (level 1 drought.)
The upcoming pattern after the upper low moves to the east favors a few dry frontal passages into the first 10 days of October. Another tropical system is expected to develop in the southern Atlantic or Caribbean and move into the Gulf of Mexico this weekend. There is an increasing threat for it to impact Florida and then move off the coast, likely staying too far south and east to bring our region rainfall.
Keep in mind even after the rain ends early Wednesday, the likely early end to the foliage season will allow the ground to dry up quickly during sunny, breezy days. The fire danger will be elevated in our region during those dry, sunny and breezy days with low humidity from mid to late October to mid-November.