Clear
skies, calm wind, and snow cover led to a quick cool down to 22F last
night before some high-level clouds and light northerly wind off Lake
Pontchartain stopped the cool down, but then it unexpectedly calmed down
again with clearing towards sunrise, with a low of 21F! However, after
sunrise, it warmed up very quickly initially with northerly wind off
Lake Ponchartrain, then the warmup slowed down, but then as the snow
cover disappeared in the afternoon, the temperature rose quickly again
up to 48F, warmer than almost all models, unlike the past 2 days.
It seems like most models showed the snow cover lasting all day today, whereas it melted somewhat faster. Such subtle details are very difficult to accurately predict, and it was a particularly sensitive situation. Surprisingly, the maximum wind was only 8 kt.
With
no more snow cover, and the overall air mass being much milder, much
warmer temperatures can be expected for tonight and tomorrow than the
past few days. Still, mostly clear skies and light winds will lead to
good radiational cooling tonight early on, but much milder given that
we're starting from a much warmer daytime temperature. A bit of
northerly or northwesterly wind could stop the cool down late in the
night. Light northwesterly winds are expected for tomorrow, slightly
stronger than today, with sunshine leading to a quick warmup unimpeded
by snow cover, and temperatures will be at least slightly warmer than today, likely exceeding most model guidance as is typical for sunny days without deep snow cover in this region. The only thing that could slow the warmup a bit is the wind off Lake Pontchartrain possibly being a slight cooling influence in the afternoon, though the water temperature is likely high enough still for that to be minimal. Also,
with a bit of cold advection aloft but warmer surface temperatures, it
will have an easier time mixing down winds from aloft, and peak winds
will be stronger than they were today.
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| Source: PivotalWeather |
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