7/5 – The Chief’s “Threat For Heavy Rain” Tuesday Morning Forecast

High-pressure is currently centered near the Texas-Louisiana border, with a north-south axis into the Dakotas early this morning with an easterly wave wrapping around the southeast side of it. At the surface, high pressure extended from central Alabama across the local area. The high-pressure will remain over the lower Mississippi River Valley for much of the week. Atmospheric moisture values remain at the upper end of climatology today, before dropping a little bit for tomorrow and Thursday. Even by Thursday, values are still going to be near or above the 75th percentile.

The easterly wave noted in the synopsis will move westward across the area today and tonight, enhancing convective development this afternoon. If current development over marine areas is any indication, areal coverage over land later in the day should be fairly high. Storms that develop today will be very slow moving and could potentially produce isolated very heavy rainfall amounts, especially near and north of the Interstate 10 corridor.

As we move into Wednesday and Thursday, the high-pressure becomes a bit more of a factor, as moisture flow drops a bit and we have no organized forcing. Areal coverage of convection will trend downward a bit each day and develop a little later in the day. Today should be the “coolest” of the next 3 days, but still getting close to 90 before convection cuts off heating. As has been the case the last few days, we’ll have some or most locations reporting their high temperatures prior to noon local time.

As we go into the weekend, drier air will move into the area for at least Friday and Saturday, with precipitable water values falling. Models attempt to push a frontal boundary into the area for Sunday and early next week, but confidence in an actual frontal passage is rather low.