Short Term Forecast:
Scattered thunderstorms may break out this afternoon across the DC Area mainly between 4pm and 6pm aided by the heat and humidity as well as a trough axis moving east from the Blue Ridge mountains.
The upcoming weekend looks relatively quiet with a mix of clouds and sunshine region wide and a few scattered showers or storms possible mainly across our southwestern zones (on Saturday afternoon). The most noticeable event this weekend will be the significant difference in temperatures from northeastern Maryland to northern Virginia as a backdoor cold front slides southwest through the region on Saturday afternoon.
Big Changes Next Week:
A pattern change is in store for the upcoming work week as we shift away from warm weather to cooler temperatures and the threat of rain.
The image above (courtesy Pivotal Weather) shows several areas of low pressure impacting the weather across the Mid-Atlantic beginning Monday and potentially lasting through Thursday.
Several areas of low pressure moving eastward from the Tennessee valley and northward along the eastern seaboard may merge and become “cut-off” underneath an area of blocking high pressure to our north.
The image below shows a bright red “blob” becoming more pronounced Tuesday through Wednesday across the Great Lakes and eastern Canada indicative of this “blocking” (think of a road block) in the atmosphere. Depending upon how the areas of low pressure interact, how slowly they move and how strong this area of high pressure becomes will ultimately determine how much rainfall we receive during the upcoming work week.
The Latest European Forecast Model
The latest European forecast model (image below, courtesy Pivotal weather) shows how the low pressure systems (at the surface) may interact across our region Monday through Thursday during the upcoming work week.
How much Rain could Fall?
Depending upon the exact movement of these features and how long they potentially stall across our region will determine whether we receive an inch or two or several inches of rain which could increase the risk of flooding. If the forecast model below is accurate, portions of the northern Mid-Atlantic from DC’s northern Virginia suburbs to Baltimore, Philadelphia, and NYC could receive more than four inches of rainfall.
More updates to come as we get closer to the event and the forecast models continue to update with new information. Until then, enjoy your weekend.