Jay Grymes
State Climatologist
cell: 225-505-6916
Friday Afternoon Winter Weather Update
These are my thoughts … the NWS is the expert resource for forecast information.
A winter double-whammy seems likely next week:
(1) bitterly cold temps statewide with dangerous windchills, and
(2) confidence increasing for measurable ‘sneaux’ across central and most southern parishes
Let’s talk temperatures first. We are expecting prolonged runs of freezing temps for each of several overnight-to-morning periods. In fact, some parts of the state may not get above freezing on Tuesday.
This kind of cold is tough on everyone … and everything. Some smaller utility companies are likely to have operational issues with the intensity and durations of these freezes. At the same time, it will be tough on many families to keep indoor temps close to comfortable.
PLEASE be judicious when using supplemental heat sources: do not leave them unattended and do NOT leave them running through the night as you sleep!
These aren’t going to be record low temperatures but they get lower and last longer than the Arctic blast f January 8-10.
As for the precipitation? It’s a near-textbook north-meets-south collision of Arctic air pouring south while a Gulf disturbance tracks near/along the coast, with Louisiana as the meeting point.
Up through early today, the NWS had been conservative (my opinion) regarding their perspective on the likelihood of snowfall. Their question was whether the Gulf moisture would arrive in sufficient doses to produce accumulations. I get it: I am usually skeptical of model-driven snow forecasts, especially out more than 3-4 days.
But this north-meets-south set-up has my attention.
Forecast models are getting MORE aggressive with the local accumulation estimates … and I believe that the NWS is getting onboard. The air is expected to be so cold statewide than any precipitation that falls will be frozen, except possibly along the coast. And even there, if it falls as rain it will create an icing concern.
In some ways, that is good news: if something has to fall, snow is generally better than freezing rain.
The state has already pulled the “closed for business” tab for next Tuesday. Now the issue is just how much snow falls, how fast it falls, and where it falls.
In this instance, northern parishes have it better than the rest of the state. That Gulf moisture feeding the precipitation will struggle to get into the northern parishes. But the way it looks now, everyone from CENLA to the coast needs to be ready to sit-out any travel on Tuesday.
The NBM (National Blend of Models) snow depiction shown here is indicating 2″ to 4″ of snow in parts of the state. I’m not “all in” on those kinds of totals, but 1″ to 2″ in places certainly seems possible (or even likely) at this point.
Guidance models are up-and-down about the accumulation numbers, but the trend has been more up than down.
Big THANKS to:
NWS Offices serving Louisiana
NWS Weather Prediction Center
WeatherBell
WeatherModels
GOHSEP & LSU
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