A weak frontal boundary wanders back and forth north and south, steered by waves in a mostly west to east jet steam this weekend. It will come back north as a warm front tonight. Warmer air pushed over the cooler air at the surface will wring out some light rain and snow. Remember the rain and snow variations earlier this week? This weak light stuff can make for a hard forecast. Let’s look at the aviation forecast to see how the NWS is trying to wrap their arms around the situation….
KHPN 302039Z 3021/0118 08006KT P6SM BKN070 BKN090
FM302200 09006KT P6SM FEW015 SCT025 BKN060
TEMPO 3023/0101 BKN025
FM010100 07006KT P6SM OVC015
FM010500 06009G15KT 6SM -SNRA BR OVC010
TEMPO 0108/0112 6SM -FZDZ OVC007
FM011400 08008G14KT 6SM -RA BR OVC011
FM011700 08008KT 6SM BR OVC012
For those of us that don’t speak “METAR” (that’s acronym is from the French – look it up!), here’s what’s important about this forecast. It forecasts light snow and rain from 12midnight (Dec 01 at 0500 in weather time), with occasional light freezing drizzle at times between 3am and 7am. The we go to all light rain after 9am, ending about noon.
So be careful if you are out in the wee hours of the morning this Friday / Saturday night for the possibility of a light glaze on the roads.
The warmer air may not be strong enough to get here on Saturday and Sunday, but warmer weather is expected to push over us for Monday and Tuesday, with another cold front and cooler weather after midweek.