Saturday, December 17, 2011

Mild And Windy This Early Morning Of December 17th

The plot above shows surface conditions across southeast Arizona at 4 am MST this early morning. Note that temperatures are again much warmer than forecast and are about 10F warmer than 24 to 30 hours ago - all of this for the second consecutive morning. Coolest readings are at the highest elevations, but I don't see any reports of temperatures at or below freezing. Here at the house the wind has blown all night, and the current temperature of 52F is also the low temperature so far - 20F warmer than yesterday morning's low! Winds are highly variable, but with highest gusts (numbers in red) at highest elevations - note 61 mph gusts on Mt. Hopkins (from the RAWS station there). The ASOS at Tucson International Airport was reporting gusts to 43 mph - the TUS wind reports are so different than surrounding stations that one has to wonder if the data are accurate (winds on the roof at Atmo are only gusting 15 to 20 mph). I assume the data are good, since they have been consistent through the night. Time series for TUS and DM are shown below for the hours since last evening. Although they are only a few km apart, the winds at DM have not exceeded 15 mph. Temperatures have been similar through the night at both sites - very mild. The time series plots of temperature illustrate the marked warm-up of the early morning temperatures during the last three days.

Finally, data from the RAWS station on Mt. Hopkins are shown below (note that 11:19 GMT is 4:19 am MST). The winds at this site (which is often very windy during deep easterly flow - perhaps due to local effects related to the higher Mt. Wrightson just to the northeast) have been blowing at speeds of 45 to 50 mph with gusts 60 mph and above - highest so far has been 64 mph. What a difference a day can make.

No comments:

Post a Comment