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Miscellaneous
Tue, 09 Feb 2010
Winter Weather Update- Tues 10:50 PM
The GFS model data just became available-- Total QPF is about 1.58 inches water. The GFS has the precip ending about 6-7 PM on Wednesday, earlier than the NAM.
So there are differences between the GFS model and the NAM model. The NAM is has 2.2 inches water and somewhat warmer. Both models have the temperatures at or just below freezing at the surface at or just below freezing up until 7000 feet. Most of the precipitation from the airport and north/west will be snow.
In past storms where there are model differences, the average of the two works well. So my updated total (with a low 1-10 or 1-12 snow ratio) is about 16-22 inches of heavy snow. I think my earlier forecast of much more, based exclusively on the NAM model, isn't going fly.
posted: Feb 09 2010 at 10:49 pm
[/weather/feb10] permanent link
Winter Weather Update- Tues 9:30 PM
Correction: The NAM data was available early tonight. QPF values have increased to 2.2 inches water, which translates into 24-32 inches of heavy snow. The new NAM prolongs the snow into Wednesday evening.
I'll update when the GFS model comes out about 10:45.
posted: Feb 09 2010 at 9:37 pm
[/weather/feb10] permanent link
Winter Weather Update- Tues PM
This morning's and afternoon NAM and GFS models have not changed appreciably from last night. Basically about 1.2 inches water. What is of interest is that temperatures are a little higher than previously predicted which may reduce snow totals. The snow will be denser and heavier to shovel.
I'll update when the new models come out about 10:45.
posted: Feb 09 2010 at 9:14 pm
[/weather/feb10] permanent link
Winter Weather Update- Tues 7 AM
Last evening's models along with the 1 AM rerun of the NAM and GFS have come together on very similar forecasts of about 1.20 inches of water (QPF) falling as snow from Tuesday evening into very early Wednesday evening. Interestingly, the WRF (Weather Research Forecast model) has 1.96 inches water falling as snow, suggesting the possibility of a bigger storm.
While I had described some uncertainties about this storm last night, I'd have to say that with so much model consistency and continuity, this snow storm is a high confidence event. Temperatures for this storm will be closer to freezing, so the ratio of snow to water may be on the lower range of 10:1 or 12:1. That means a heavier snow to shovel than the last one. With current QPF values, a 12-24 inch snowfall is what we'll receive, with 15-18 inches most likely.
By the way, the heaviest snow will be falling before daybreak tomorrow and during the morning hours.
I'll be at work during the next model output later this morning, but I'll try to use my iPhone to update the website if expected snow totals change significantly.
posted: Feb 09 2010 at 7:07 am
[/weather/feb10] permanent link
Disclaimer: I am not a meteorologist and provide this information as a hobby and for entertainment (mostly my own :-) . While attempts are made to predict the weather as best as I can, use at your own risk! I am NOT responsible for any direct or indirect consequential injury/damages due to your use of these forecasts. Always check the NWS Official Forecast for your final plans.
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