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Posted at 05:00 AM ET, 08/14/2012

Forecast: Humidity and storm chances increase today; much cooler by Sunday


Today: Mostly cloudy. Mainly PM storms. 87-90. | Tonight: Mostly cloudy, showers, storms. 65-70. | Tomorrow: Partly cloudy, slight shower/storm risk. 87-90. | Get Express Forecast by E-mail


A somewhat subjective rating of the day’s weather, on a scale of 0 to 10

Increasing humidity and pm storm risks keep us toward low side, but still much better than July heat. Get the Digit on Twitter| Discuss on Facebook


Two cold fronts in three days suggest that the pattern is becoming more active. This pattern prevents big hot and humid air masses from locking in and intensifying. This is good news for everyone tired of the record heat we experienced last month. The first cold front this evening could produce some storms but then helps to knock the humidity down a bit Wednesday and Thursday. The second, stronger cold front Friday evening into Saturday delivers a shot of even cooler, drier air by Sunday.

Today (Tuesday): Variable to mostly cloudy skies today with a 40-50% risk of showers and thunderstorms (mainly in the afternoon, with a smaller chance in the morning). Highs should be in the mid-to-upper 80s, but a few spots could reach the 90-degree mark. Dew points (humidity levels) are on the rise, so the discomfort level edges higher too. Some of these later day storms could be severe with gusty winds and hail. Winds from the south and southwest at 5-10 mph. Confidence: Medium

What is the Storm Threat Level?

Tonight: The cool front takes a while to fully traverse our region, so showers and thunderstorms continue to affect the area, especially this evening, but potentially up through around midnight or so. The likelihood of precipitation is 60% as many areas should see something. Again, these evening storms could be severe. Total rainfall for the day and night should range from .25” to .5”, locally higher. Light winds from the southwest and west except around thunderstorms. Lows in the mid-to-upper 60s in the suburbs to around 70 right in the city. Confidence: Medium

For related traffic news, check out Dr. Gridlock. Keep reading for the forecast through the weekend...

Tomorrow (Wednesday): Partly sunny skies, still warm, but with a reduction in humidity by afternoon, especially in areas from the city west and north. Highs should reach the mid-to-upper 80s. The back edge of the departing cool front could be close enough to trigger a scattered shower or storm mainly south and east of the city (20-30% risk). Light winds from the west. Confidence: Medium

Tomorrow night: Partly cloudy, cooler with lower dew points and light winds. Lows in the low-to-mid 60s in the outer suburbs to mid-to-upper 60s in the city. Confidence: Medium


Thursday is a decent day with relatively low humidity, light winds, and sunny skies. Highs head to the mid-to-upper 80s to 90 in some spots, but the lower dew points (humidity) make the warmth far more comfortable. Thursday night looks partly cloudy and a bit warmer with lows in the mid-60s to around 70 in the city. Confidence: Medium-High

Friday aims to be our hottest day of the week with humidity back on the increase, highs in the upper 80s to low 90s, and a 30% chance of afternoon thunderstorms due to a cold front approaching from the west. By Friday night, the odds of storms increase to 40% with mostly cloudy skies and lows in the upper 60s to low 70s. Confidence: Low-Medium

The weekend starts off a bit messy and muggy with thunderstorms likely on Saturday (60%) along with moderate dew points. Highs should only be in the low-to-mid 80s though. We trend cooler Saturday night, but could still see a few showers and lingering clouds. Lows in the low-to-mid 60s. Sunday looks partly sunny and much cooler with highs only in the upper 70s to low 80s (and this is with relatively low humidity too!). Confidence: Low-Medium

By  |  05:00 AM ET, 08/14/2012

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