* Heat advisory noon to 7 p.m. for District and close-in suburbs *
FORECAST IN DETAIL
A powerful dome of high pressure stalled over the area is stifling us with stagnant heat and humidity for the next few days with very few storm risks to cool us off. Records from today through Friday range from 102 to 104F. We’ll stay below those levels but, factoring in the humidity, heat indices soar to the 101-110F range during the hottest part of each afternoon.
That high pressure cooker starts to break down by later this week, but the cold front cavalry doesn’t get here until Saturday, possibly carrying severe storms. Then cooler weather arrives by Sunday finally.
Today (Tuesday): Our week long oven-baked adventure continues today as temperatures should creep up a degree or two higher than yesterday under mostly sunny skies. Humidity levels should be about the same, so highs in the mid-to-upper 90s, feel like the low 100s to maybe around 105 or so. Light breezes from the north offer but a pitiful attempt to relieve our unpleasant air mass. Confidence: High
Tonight: Moderate to high humidity means that temperatures are slower to cool in the evening hours, so discomfort levels remain high even as the sun gives us our nightly time out. A few scattered clouds are possible. Lows drop into the low 70s well after midnight in the outer suburbs, but hold in the upper 70s right in the District. Very light breezes again from the north. Confidence: High
For related traffic news, check out Dr. Gridlock. Keep reading for the forecast through the weekend…
Tomorrow (Wednesday): Mostly sunny and seriously hot yet again with highs in the middle to upper 90s, moderate to high humidity, and heat indices in the 101-105F range. Light breezes mainly from the north yet again. There is a 20 percent risk of a widely scattered thunderstorm in this pattern, but that chance is probably higher toward the mountains. Confidence: High
Tomorrow night: Partly cloudy, muggy, and very warm with lows again ranging through the 70s (low for suburbs and upper for inner city) with just light breezes. Confidence: High
A LOOK AHEAD
Thursday and Friday continue to bake at full blast with some assistance by a slightly stronger westerly flow. This could allow temperatures to more uniformly be in the hotter upper 90s with a few spots potentially hitting 100F. Heat indices should range from 101-110F during the afternoon, so please limit your outdoor activities and drink plenty of (non-alcoholic!) fluids if you are out and about. Thursday and Friday night see muggy lows in the 70s again, but I honestly wouldn’t be surprised if National Airport only got down to about 80 degrees. There is a very slight risk (20 percent) of widely scattered thunderstorms during the afternoon or even the overnight in this pattern. Confidence: Medium-High
The weekend brings relief in the form of a cold front and attendant showers and storms later in the day on Saturday into Saturday night. Some storms could be strong to severe. Highs Saturday could still manage the low 90s with moderate to high humidity before clouds and precipitation risks overwhelm the situation. Saturday night sees a bit cooler weather with lows in the low-to-middle 70s. Sunday may see a lingering 40 percent risk of storms, especially in the southern half pending where the cool front decides to sit (still lower confidence on this issue). But either way, we should still see highs below 90 (middle to upper 80s) for the first time since last Sunday. Confidence: Low-Medium