today the models flipped there stances the nam is now cooler and the gfs warmer. My thinking with a low track from bwg to lex to maysville only areas south and east of this line will see substantial warm air advection with areas near the track of the low to see about a 8 hour window for snow ( bwg 01Z-09Z), (Lex 06-14Z which is centered around the rush hour) and maysville after that. areas such as jackson, Pikeville and London will see a quicker transition to rain with Ashland perhaps being far enough north for only a brief mix. During this transition a little ice may mix in but that should be very minor.
here is a timeline of the 00z nam with precip maps which take into account the thermal profile of the entire atmosphere and project precip type based on that data.
4 am Tuesday pink is snow and green is rain
7am Tuesday
10 am Tuesday
1 pm tuesday the cold front is crhasing through
5 pm tuesday
notice how the cold air catches up with precip shield for a period of snow at the end this could bring another 1/2 inch to a few spots.
snowfall forecast
Timeline
– period of snow regionwide from monday night into tuesday morning
– the snow changes to rain in most areas that are in 1 or 1-3 , the main reason why totals are down is b/c qpf has decreased on recent runs
– temp spike in the mid 30’s along the track of the low tuesday morning near 40 southeast of jackson early in the afternoon
– nw winds increase as the front passes and temps crash likely resulting in icy spots another light snowfall up to 1/2 inch may occur as the cold catches the precip shield, this is included in the snowfall forecast.
uplsope snows from Tuesday night into wednesday which is the next event as usual the se mountains will be favored, ironically the areas that will get less from tuesday’s event. the wind direction off the lakes will determine where the bands of snow showers set-up with temps in the 20’s ratios could be around 15:1. Here is the 12z gfs which is a little overdone though.
I could see an inch or so for most central and northern locations, a light coating south and west with a couple of inches southeast as of now. I haven’t had time to look at this warp around event closely yet.
Also taking a look some of the models are wanting to trend friday’s system north to give folks from bowling green to Pikeville another snow chance.
12z jma
This snowy and cold pattern should continue into mid march, we’re not done yet by far!!
February 7, 2010 at 11:26 pm |
00z nam slightly colder again.
February 7, 2010 at 11:52 pm |
00z models trended colder full update after the 12z runs.
February 8, 2010 at 12:17 am |
What time is that Mitch?
February 8, 2010 at 12:49 am |
next update late tommorow afternoon with final call.