Gray, Cloudy Afternoon In Tucson

Has been a gray and dreary afternoon here in Tucson (see above), as abundant high and middle cloudiness streamed in from the Pacific. Current water vapor image (below) shows a broad, trough at low latitudes, which has pulled the cloudiness in ahead of it. Note that there are two, unusual, upper-tropospheric waves west of San Diego, that have been very persistent as they roll eastward. The strong cyclone off of northern California is quite impressive at this time in staellite imagery.

The 12hour (valid 5 pm this afternoon) NAM forecast for 500 mb (above) shows the northern short wave and the broader trough to its south and southeast. Models forecast the northern feature to weaken as it moves across Arizona on Monday, with perhaps a brief round of light showers. A stronger system may impact the Southwest on Thanksgiving Day - but the various models are bouncing around for the Holiday, as per discussions on the SUNY MAP board re chance of strong winds during Macy's parade.

Finally, a November tropical system has developed in the eastern Pacific - TD-13E. First NHC fiorecast for this TD is shown above, indicating some strengthening and possibly a hurricane in its future.