Arctic Cold Leaving, Huge Warm Up Brings T-storms

As most of you know, I don't like real cold weather.  Today is as cold as I want it, but if you were dressed for it, it actually felt pretty good.  No, it wasn't warm enough to golf or fish, but I didn't feel bad running errands under bright sunshine.  It started cold at my house and I was glad I brought my plants into my He-Shed.  Tonight will be almost as cold as winds have died and skies are clear, but that's about to change.

You can see the frontal boundary draped well off our coast with a thick cloud cover back inland over Texas.  As the Arctic high shifts to the east, winds will return off the Gulf bringing back the muggies and warmer air.

With dew points in the teens and 20s, it will take a while for the atmosphere to moisten up. Saturday will be dry with increasing clouds, and Sunday through Tuesday will have multiple rounds of showers and T-storms. WPC and NWS are forecasting the potential for heavy rainfall (3-5"+) resulting in possible street flooding. The top graphic shows the 5-day rain totals, indicating the heaviest just to our north and west.

The flood threat has been increased to a level 2 for Monday.  What will cause the change in our weather?  Meteorology 101 says the cold side of high pressure has the north winds while the back side has the southerly winds bringing back warmer air & humidity.  Add in an approaching upper disturbance and we have the ingredients for strong storms.  Let's begin with now. A disturbance west of Washington will provide the "kicker" to the forming upper low over the Southwest.

That SW upper low will race to the NE well north of us.  As it does, it leaves us in a SW upper flow that will stall the rain boundary across south Louisiana. The top graphic is this morning with the low over the SW.

By Sunday morning, the upper low moves into West Texas. Below is valid for Monday morning followed by Wednesday AM. Note the low never digs towards the SE allowing for the front to stall.

A deeper trough will develop by Wednesday AM (bottom graphic) bringing us our next round of colder weather.   Right now, it doesn't look any colder than the current chill.

I think our best rain chances arrive Sunday night into Monday morning with another round coming on Tuesday.  Remember, 80% chance doesn't mean it will rain 80% of the time.  There will be many dry hours between storms.  One thing to be looking for is if the "training effect" sets up.  IF you get caught under a stalled band of storms, it might rain 100% of the time with excessive rain amounts.  I called it "pay attention" time.  Now it's called 1st Alert, 1st warning, Weather impact days.  Whatever, just pay attention late Sunday into early next week.  

Don't forget this Saturday night is the annual Christmas Art Stroll on Magazine Street.  I'll be at Degas Gallery 6-8 PM helping my wife Brenda show off some of her art work.  Come stop by and say hello.  For tonight, Go Wave!  Stay tuned!