:: Fire Weather (Part 2)
Forecasting a dry spell is no fun...and we have entered a relatively dry run for the range. Only a slight anomoly to the ongoing zonal flow this week and next, and that is an increase in southerly moisture in the low-mid levels into the early weekend. The polar jet is stuck up along the Canadian shield again, keeping us out of the fray so to speak. Models show theta-E edvection building a ridge along the Couteau des Praries and stretching across central MN by Saturday afternoon. This is coupled with more creedence for precipitable water values on the increase for raising slight chances as early as Friday into Saturday for splash-and-dash shower activity. Diurnal heating will trigger them, but capping may be of concern as we remain far south of the jet. Should MOS temps hold, plus a healthy buffer, the cap could be almost a foregone conclusion...ETA CAPE forecasts teast at 1000+ J/kg for Sat PM but again any capping will keep instability at bay.
GFS definitively paints an upper-level trough to cross northern MN and WI Saturday night...also prominent upper jet max exiting in this region...right now left front exit is progged over Kenora...but ETA depicts jetlet exiting over eastern Lk Superior. Should jet sag even 100 nm south, DLH and western Lk Superior region may see good svr weather event as result. Long wave trough currently developing in lee of Rockies should genesis to cold front due to pass through our area by Sunday. Precipitable water, advection, and timing around potential cap will determine any precip chances thru weekend. For now I will stick close to MOS guidance for much of forecast...
THURSDAY...Mostly Sunny, High 85. Light winds from W-N. Low 62
FRIDAY...Mostly Sunny in AM, Turning Partly Cloudy after lunchtime, High 87. Winds turning SW 5-10 mph. 30% chc showers after 3pm. Low 65
SATURDAY...Partly Cloudy, Humid, and Warm, High 92. 30% chc thunderstorms after dark. Low 62
SUNDAY...Clear and Dry. High 85. Low 60.
OUTLOOK WEEK OF 7/10/06... Hot and Dry....highs at or abv 90. Slight Precip chances again Wed night into Thurs.