00Z Tu 10 May 2011 Forecast Discussion

Situation evolving not too differently than suggested by yda's forecasts ... deep surface low is nearby, with winds on the flats having veered from SSE to SW previous hour with some blowing dust visible on the Siemans cam.

Expect surface circulation will continue to take shape near the CO-WY-NE triple point next couple hours and that as this happens winds on the flats will continue veering into the W. Whether they will continue to veer and go into the WNW is possible; winds are likely to continue quite strong over the next few hours, peaking early to mid evening. Another uncertainty is pcpn ... there is widespread shower activity on the western slope attm, as well is in SE WY. I am less optimistic about pcpn on the flats than yda, as it looks as if the showers are going to stay mainly W of the Divide S of Berthoud Pass. This puts the flats on the southeastern edge of the shower activity, as cells from the western slope cross the Divide mainly north of Berthoud Pass and dissipate as they move off the Divide. I put the likelyhood of measurable rain on the flats between now and midnight as 30%, chance of some pcpn at all during that same period, including very light from small drops, as 60%.

Probability of M2 peak gusts exceeding 15m/s ........... 25m/s

00-06z ............................................. near 100% ...... 60%

06-12z .............................................. 60% ................ 30%