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Posted at 05:00 AM ET, 07/02/2011

Forecast: Heat builds before 4th of July

8:15 p.m.: One lone storm is weakening while heading into the area from the north. Portions of eastern Loudoun, western Montgomery and maybe into Fairfax/Arlington counties could see some brief rain and a rumble of thunder or two over the next 30-45 minutes, if the cell holds together, which it should not do for long.

Today's Daily Digit
 
A somewhat subjective rating of the
day's weather, on a scale of 0 to 10.

 
Tempted to go up 1 from Friday for increased humidity, but that might be confusing. July is hot in D.C.!
 
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EXPRESS FORECAST

Today: Mostly clear. Near 90 to low 90s. | Tonight: Partly cloudy. Shower late? Upper 60s to lower 70s. | Tomorrow: Partly to mostly cloudy, shower or t’storm possible. Low-to-mid 90s. | 4th of July: Partly cloudy, slight risk of t’storm. Near 90 to low 90s. | A Look Ahead | Get Express Forecast by E-mail

FORECAST IN DETAIL

July averages 14 days above 90F in D.C., and we’re off to a solid start tallying ‘em up here in the beginning of the month. It seems a pretty good bet we’ll add a few more in the coming days. The other typical July threats around here — humidity and t’storm chances — will also be around, though perhaps in somewhat subdued fashion overall. Fingers still crossed that we see clearish skies and a bit of a breeze heading into the evening festivities on Monday.


Radar & lightning: Latest D.C. area radar shows movement of precipitation and lightning strikes over past two hours. Refresh page to update. Click here or on image to enlarge. Or see radar bigger on our Weather Wall.

Today (Saturday): Summer forecasting is sometimes a welcome respite from thinking hard, especially in a benign pattern. Remember yesterday? Bump temperatures and humidity a notch and you’ve got today. Highs reach near 90 and into the lower 90s as those glorious dew points in the 40s yesterday creep back toward a moderately muggy 60 later today. It’s largely sunny, with perhaps some increase in clouds by evening. Confidence: High

Tonight: Clouds increase as a cold front and a wave of activity out ahead of it come our way. It should be dry and fairly comfortable though, with temperatures falling to the upper 60s (mid-60s in the coolest spots?) and lower 70s. I said should be dry, because if you’re out after midnight there’s a slight risk (20%) of a passing sprinkle or shower. Confidence: Medium-High

Keep reading for the forecast through Independence Day and beyond...

Tomorrow (Sunday): The cold front moves into and through the area during the day. What it does while passing by is a bit uncertain still. Guidance wants to spit out plenty of clouds and scattered storms, but also plenty of warmth. So, partly to mostly cloudy conditions seem plausible, with an increased risk (40% chance) of a passing storm during the afternoon — best chances probably south as the front arrives there latest. Highs should strive for the mid-90s, but with a lot of clouds it might be more like low-to-mid 90s. Confidence: Medium

Tomorrow night: The front should settle into southern Virginia, but it’ll be a slow process and it does not get too far away for now. This means decent cloudcover probably remains overhead, with an outside risk (20%) of a shower. Lows reach the upper 60s and lower 70s. Confidence: Medium-High

A LOOK AHEAD

What’s the Fourth of July looking like? Well, as noted above we’re hoping for the best. The cold front should stay to our south far enough that we remain largely dry, and hopefully only partly cloudy. Still, can’t rule out at least a pop-up storm (30%) given summertime heat and a touch of humidity. Highs should reach near 90 to the lower 90s. Confidence: Medium

On Tuesday, as we eagerly race back to work, we’re still in a summertime pattern. A positive for clear-sky lovers is that the front should push further off to our south, so sunshine is probably featured throughout. “Cold front” is misleading at this point, with highs still up near 90 or into the lower 90s. Such is July in Washington. Confidence: Medium

By  |  05:00 AM ET, 07/02/2011

Categories:  Forecasts

 
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