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Posted at 05:00 AM ET, 07/25/2011

Forecast: Not as hot, chance of storms; extreme heat to re-load mid-to-late week

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

 
Still uncomfortably humid. But at least no triple digit heat index & any rain is welcome.
 
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EXPRESS FORECAST

Today: Mostly cloudy, humid. 50-60% chance of storms. 87-93. | Tonight: Evening storms, then partly cloudy. 67-75. | Tomorrow: Mostly sunny, very warm, not as humid. 90-94. | Get Express Forecast by E-mail

FORECAST IN DETAIL

Each day last week the high temperature reached at least 90, and odds are good we do it again for the entirety of this week. The lone wrinkle is today’s forecast when clouds and storms could keep temps below 90 in a few spots. While we may not get a break from 90-degree heat, we will get a short break from oppressive humidity Tuesday and Wednesday before it rejoins the heat Thursday through Saturday for another potentially oppressive stretch.


Radar & lightning: Latest regional 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 (Monday): For the fifth straight day, downtown temperatures likely start the day at or above 80, with mid-to-upper 70s elsewhere. The humidity is high to boot. In other words, you may feel the need for a shower by the time you get to work. Considerable cloud cover slows the ascent of temperatures and it won’t be as hot as the last four with highs only around 90. Still, we may see a few heat index readings near 100. A slowly approaching cold front brings the chance of showers and storms, with the best odds in the late afternoon into evening (50-60%) - odds before that are just around 20-30%. A few storms may produce torrential rain and isolated damaging wind gusts. Outside storms, winds are from the south around 10 mph. Confidence: Medium-High

Thundercast:

Probability: 50-60%
Coverage: Scattered
Most Likely Timing: Mid-afternoon through evening

Tonight: We have a decent chance of thunderstorms this evening - probably as good as we have all week, although it’s no sure thing. After 9-11 p.m., any storms wind down. Some modestly drier air works in, with lows from the upper 60s in the cooler suburbs to the mid-70s downtown. Confidence: Medium-High

Keep reading for the forecast through the weekend...

Tomorrow (Tuesday): We kick out the moist, tropical air mass and finally get into some drier flow from the northwest (around 10 mph). Although the air is less humid, it’s not quite refreshing with dew points still in the low 60s. Ample sunshine pushes highs into the low 90s. Confidence: Medium-High

Tomorrow night: Probably the nicest evening of the week for outdoor activities with temperatures falling back through the 80s (beats the 90s) before midnight with manageable humidity levels. Overnight lows dip as low as the mid-60s in the cooler suburbs to the low 70s downtown.Skies are mainly clear. Confidence: Medium-High

A LOOK AHEAD

Wednesday is much like Tuesday: lots of sun, moderate humidity, and highs in the low 90s. The breeze is from the north but too light to take much of an edge off the searing afternoon sun. Wednesday night, winds shift around to out of the south increasing humidity levels and setting the stage for the next sauna-like stretch. Lows range from near 70 in the cooler suburbs to the upper 70s downtown. Confidence: Medium-High

Like the week before, Thursday through Saturday stand poised to produce a round of scorching hot days, Friday being the hottest. Highs Thursday and Saturday probably reach at least the mid-90s, with Friday at least the upper 90s. Factoring in the humidity, heat indices may reach 100-110+. Little relief at night with overnight lows ranging from the muggy mid-70s to low 80s. The details with respect to exactly how hot it gets are still a bit fuzzy and these numbers may need to be adjusted upward or downward. Rain chances during this stretch are small (10 percent chance of isolated late day storms, maybe 15-20% Saturday). Confidence: Medium

A weak cold front (with very limited moisture) passing through Saturday night may knock temperatures and a humidity down a notch for Sunday, but not significantly. Highs appear likely to reach 90-95 with more sunshine. Confidence: Low-Medium

By  |  05:00 AM ET, 07/25/2011

Categories:  Forecasts

 
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