10 Oct KBIL forecast

Post date: Oct 10, 2012 8:10:08 PM

strong cold front currently along the Canadian border poised to dive south overnight, bringing a complete shift to the weather at KBIL. Currently, to the north of this front, temps are in the 40s with overcast skies and some light precip, south of the front skies are clear with temps in the 60s. Model forecast quickly brings this front through KBIL this evening with winds shifting around to be out of the NE overnight and for most of the day tomorrow. NAM QPF shows some light precip over most of the state during the day, with a good easterly component there upslope flow, so expecting low clouds for (almost) the entire day tomorrow, With fast flow aloft, the anticyclone is predicted to quickly move off to the east, pressure gradient should switch the winds to more of a southerly component by sunset, so there could be a brief hour or so of sun to throw a potential curve-ball at us for their max temps. Another tricky issue: guidance values for temps are all over the place again today, GFS MOS has their min temp tonight getting down to 31, NAM MOS shows 37 (NWS agrees) which is more consistent with meteograms which are showing upper 30s. Clouds should arrive well before sunrise, so it is possible that they will not even drop below 40 overnight. Max temp guidance valuees are all in the low 50s, although NWS currently has a max of 48, which seems reasonable if you are going with overcast skies for the entire day. Hard for me to believe the POPs in MOS guidance are so low, below 10% in both GFS and NAM, even with NAM meteogram showing 0.01" during the day tomorrow. NWS POPs of 30% look much better, although doesn't look like there will be much more than 0.01" of precip, so it won't have much of an impact on your score either way if you decide to go zero or a hundredth (or two). I won't be surprised if they end up seeing several hours of light drizzle adding up to a trace, which is scored as 0.00". Winds are predicted to remain relatively light, considering the decent pressure gradient that is a bit of a surprise to me, NAM BUFKIT soundings showing ~15kts at 500m above the surface during the day tomorrow, it will be tough to mix that momentum down to the surface given the cool/stable air. I expect the consensus values to be around 51/36/12/0.01" with a decent amount of spread in the temperature values given the wide range of MOS numbers that we're currently seeing. I got "burnt" Monday going too cool, so the temptation for me will be to go a bit warmer on the max temp, I'm going to try to resist that temptation.