Additional heavy rain possible through Tuesday
The wet pattern continues today and into tomorrow with scattered showers and thunderstorms in the forecast. The chance of severe weather is low, but an isolated strong storm is possible.
Today and Tonight: The final full week of May will begin wet. Cloud cover will dominate the day, with periods of rain and thunderstorms. The overcast skies will keep thermometers in the upper 70s. All of the 13 Parish, 3 County forecast area will pick up measurable precipitation. However, the rain will not be constant, breaks are expected. The heaviest thunderstorms could bring downpours and a quick inch or two of rain. Action will continue to be scattered about overnight with readings stopping in the upper 60s.
A *FLASH FLOOD WATCH* remains in place for the entire forecast area through 7pm Tuesday. A stalled front will bring multiple rounds of heavy rainfall over the watch area. Much of the area has already received heavy rainfall over the weekend which has resulted in a saturated ground. Additional heavy rainfall from thunderstorms is expected to produce storm total accumulations generally between 4 and 7 inches through Tuesday evening. Some locally higher amounts are expected. This will result in rapid runoff and possible flash flooding. In addition there could be some minor river flooding issues as well. A *FLASH FLOOD WATCH* means that conditions may develop that lead to flash flooding. Flash flooding is a very dangerous situation. You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued.
Up Next: The unsettled weather will continue through Tuesday. While rain coverage may not be as robust tomorrow, some storms will still have the potential to produce heavy rain. This is all in advance of a cold front that will fully push through the area by Wednesday. After that, some cooler and drier air moves in. Don't expect a big drop, but highs will stay in the 70s Wednesday and lows will sink into the mid 50s Wednesday night. We will then stay sunny into the weekend with the chance of an isolated shower returning on Sunday. Temperatures will rise as well, and while we'll be cooler on Wednesday, temperatures approach 90 again by the weekend.
Runoff from rain in the local area will not make it into the rising Mississippi River. The highest crest in several years is expected for “big muddy” in Baton Rouge. Here is what to expect.
THE SCIENCE: A cold front has moved into the area and will remain draped across the region through Tuesday evening before finally getting a renewed push southeast early Wednesday morning. The upper level low spinning over the western Great Lakes region will remain there through tonight and then dig southeast Tuesday. This will keep the area under southwesterly flow aloft which will bring multiple disturbances across the region. Combine that with very rich moisture and showers and thunderstorms still look like a certainty. The issue as has always been is where these rounds of storms develop and track. A shift of only 50 miles can make all the difference from seeing 1-2 inches of rain to 5-7 inches or more of rain. The next round of rain and thunderstorms is expected to develop Monday afternoon and evening. Storms should still be rather efficient given the amount of moisture we have to tap into and instability in place. As a result, the flash flood watch will remain in place as some locations received 5 to 7 inches of rain just yesterday. The ground is quite saturated and this should lead to faster runoff. The potential is still there and again it only takes minor deviations to see a large difference in rainfall. Confidence in is not as high as Sunday with respect to the coverage of heavy rain, however still expect to see a few locations with 4 to 7 inches or more added on to what has already occurred. A longwave trough will continue to dig across the central CONUS Tuesday night and Wednesday morning with the trough axis finally swinging through Wednesday evening. As this occurs rain will finally shut off but prior to that we could still see a few showers. The cold front will finally surge south with cooler and drier air moving in. Enjoy the pleasant conditions while you can as the air mass will be quite transient with return flow already back over the region early Friday morning. In fact the pattern is progressive enough that it now looks like we could see some rain return next weekend.