Lehigh Valley under flash flood watch through tonight, with torrential rain expected in some areas
By Stephanie Sigafoos
The Morning Call |
This graphic from the Storm Prediction Center shows the Lehigh Valley at risk of severe weather Thursday, July 11. The National Weather Service has issued a flash flood watch. (NWS/SPC)
The Lehigh Valley and surrounding areas have been placed under a flash flood watch from 2 p.m. this afternoon through late tonight, the National Weather Service said.
Showers and thunderstorms expected to move through the area will be capable of producing torrential rainfall, with local amounts of 1 to 3 inches and higher amounts possible in a short period of time, the watch states.
The risk of flash flooding is highest in urbanized and low-lying areas. Rapid rises on small creeks and streams is possible.
July has been the only month so far this year where precipitation in the Lehigh Valley is near normal. So far this month we've had 1.94 inches of rain in Allentown, or .40 above normal.
This latest climate report from NOAA has eye-opening numbers for the nation and Lehigh Valley »
In a report this week from the National Oceanic and Atmospheric Administration's National Centers for Environmental Information, data showed there has never been a wetter 12-month period in the lower 48 states than the last 12 months. The same holds true for this area, all of Pennsylvania, and a large portion of the Mid-Atlantic region.
The last time the area had a departure from normal in precipitation was October. A total of 3.25 inches of rain fell that month, -0.63″ below average.
Severe Potential:
The weather service and the Storm Prediction Center say a lack of cloud cover through the early part of the morning will allow sufficient heating, with temperatures rising into the 80s across the area. Breaking down the afternoon/evening, forecasters say:
There is plenty of moisture and heavy rain will "be a big threat".
Additionally, there is an indication potential exists for storms to backbuild and train over some areas.
While wind profiles are seen to be relatively weak, meteorologists have noticed veering (a clockwise shift in wind direction) with height. This may allow for some rotation to occur, so a tornado cannot be ruled out.
Models continue to show swaths of 2-4″ of rain with these storms today, but exact locations have not been well modeled.
The weather service says given wet antecedent conditions and low flash flood guidance, especially through the Lehigh and Delaware Valleys and neighboring areas, it seemed prudent to highlight the flash flood threat for today.
Looking Ahead, What About Barry?
The weather service says dry conditions are on tap from Friday afternoon through at least Sunday morning. Highs will generally be in the 80s to around 90 during that time, with dewpoints falling from the 70s on Friday into the 60s through the weekend as the airmass dries out.
NEW: Hurricane and Tropical Storm Watches have been issued for much of the Lousiana coast. Future #Barry is still expected to make landfall along the Lousiana coast Saturday afternoon as a hurricane! pic.twitter.com/xdPVfiYZOq
— Empire Weather LLC (@empirewx) July 10, 2019
Potential Tropical Cyclone #Two Advisory 4: Disturbance is Not a Depression Yet But Expected to Be One Soon. https://t.co/VqHn0u1vgc
— National Hurricane Center (@NHC_Atlantic) July 11, 2019
Meanwhile, during this time, what is currently Potential Tropical Cyclone Two may become Hurricane Barry over the Gulf Coast, and will lift north into the Mississippi Valley over the weekend. The remnant low then looks to meander over the Midwest through the middle of the week, until possibly affecting our area late next week.
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