Saturday, October 22, 2016
Unsettled For Last ten Days Of October
Nice sunrise this morning - Saturday October 22nd.
Several 500 mb short waves will affect the Southwest during next 10 days and subtropical moisture has been inching northward. The GEFS plumes from 06 UTC last night (below) forecast slight chances for showers tomorrow into Tuesday. The operational GFS (blue), which is formulated differently than the GEFS members, is a serious, wet outlier.
I've looked at the WRF-GFS from 00 UTC last evening because it runs out to 7 days (but, I don't know what the GEFS plumes were from that run). Regardless, above is the forecast for total precipitation through 6:00 am MST on Tuesday morning. Things get more interesting later in the forecast period and below shows the forecast of total precipitation through 5:00 pm on Saturday October 29th. If this were to verify, October would close out with a significant and widespread precipitation event for Arizona.
These two forecasts from the same run illustrate some of what the model brings into confluence over Arizona. Forecast above of PW shows a significant intrusion of high PW up the GoC and into Arizona at 4:00 pm on the 28th, with amounts well over an inch. At the same time (below) the model indicates a fairly strong short wave to be moving into Arizona and northwestern Mexico. Again, this would be a very interesting, and welcome, end to the month, were the forecasts to verify well.
Posted by Bob Maddox at 8:28 AM