Written at 3:30am
Overnight model runs continue to show excellent consensus among the models in timing and high amounts of precipitation coming over the next couple of days. The overnight high-resolution run of the 3 km NAM model shows copious amounts of rain and snow headed this way. As has been the case most of the time with these storms, I am not ready to jump off the cliff proclaiming the overnight run of the NAM 3km high-resolution model as my guide. The morning run of this model is usually more accurate. I will share that data on my 9 am update.
The models show moisture and precipitation gradually increasing throughout the day, from the highest elevations early to the lower elevations later today. All models show the heaviest snow from midnight until 8am Thursday morning. Looking “upstream” there are very few radar echoes in Arizona, but they are gradually increasing. Their winter weather highlights start in about 2 hours. In our area, snow showers are already breaking out from San Juan County and to the north. This indicates excellent moisture transport.
The parent low is still off of the California Coast and, the plan is, at least according to all of the models and forecasters, that as the low moves northeast it will rotate a huge pool of moisture from the south which will interact with a longwave trough stretching from Idaho to Central Baja in Mexico. This will pull all of the elements together for the entire four corners area. It is quite something to see on the surface map-if it is correct, again I will wait to see the next surface map. Then I will go into more analysis on that on my 9 am Update.
For now, here are the latest full runs of the Canadian, Euro and GFS.
The Canadian liquid output
The Winter Storm Warnings in Arizona were just updated, the trend there is for higher top-end amounts, and Payson and Prescott have been added to the affected areas.
Next update at 9am
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