Freeze Warnings Tonight, But Will Clouds Save Us?

I was watching Bruce Katz's 4 PM program showing graphics that outline tonight's freezing temperatures.  I've prepared my yard so I'm ready, but I'm not sure it'll get that cold.  Why not?  Satellite views have clouds lingering and they could help keep most areas south of the Lake above freezing.  The North Shore will not be as lucky.

Computer models have the clouds leaving early this evening, but that's not what I'm seeing on satellite loops.  Hopefully you have protected whatever plants you want to save?  Rather you error on the side of caution.  

IF we can get the clouds to leave, this weekend looks beautiful, IF you're dressed for it.  The core of the brutal cold will remain well to our north & east, but don't look for any rapid warm up during the next 7-10 days.  Here's why.

All during late November through December, we had an upper trough along the West coast with an upper ridge over the SE.  That resulted in our warmest December on record.  But as you can see, that pattern has flipped with the Ridge off the West coast and a trough over most of the nation.   That has brought down Arctic air into the lower 48, but this is not record breaking/extreme cold.  The super cold (30-35 below) remains well up over northern Canada.

The cold we now have is well below our average/normal, but it's typical late January weather better we get the cold now and not during the Mardi Gras parades!   Since this is very dry air (note dew points in single digits west), IF winds decrease and clouds leave, a hard freeze(23-27) north of Lake P. appears likely not only tonight but again Sunday morning.

And if you think Lake Pontchartrain will save us on the South Shore, think again because the Lake's water temp. has dipped into the upper 40s reducing the warming effect.  Only the clouds can save us for tonight.  Sunday morning will be even colder.

Finally, in case you haven't been paying attention, a big surge has moved down the Mississippi due to the rains & snows up north.  We've gone from 3 feet at the Carrollton gage to over 10 feet today with another foot to go before the River starts falling next week.  There is no need to run the water tonight UNLESS you live on the North Shore.  Check the temperatures before you go to bed.  If it's still 35-40, you won't see a hard freeze.  But if it's already below freezing, run a pencil thin flow of warm & cold water.  No need on the South Shore.  Bundle up & stay tuned!