Forecast Discussion
000 FXUS65 KTWC 210931 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 231 AM MST Tue Mar 21 2023 .SYNOPSIS...A strong storm system will affect the area through Wednesday night with periods of strong winds today into Wednesday and scattered showers mainly on Wednesday. It will also usher in much cooler temperatures Wednesday into the weekend. && .DISCUSSION...A strong storm currently approaching the California coast will gradually translate eastward while filling. This system will have a variety of significant impacts for Arizona, heavy precipitation for central and northern parts of the state and periods of strong and gusty winds for southern Arizona, our focus. Ensemble solutions continue to suggest central and western Pima county are potentially looking at a climatologically significant wind event with the NAEFS showing it at a greater than 99th percentile event for late March and the ECMWF EFI also showing this area to also be well outside climatology. Tweaked the winds in this area a bit and we also decided to hoist a wind advisory for that area east to Cochise County at this time. This has been debated the last couple of days as not every locations within the advisory area will meet criteria and it isn`t expected to be consistently windy everywhere either. With typical storm systems the Sierra Vista area can get cranked up, however this storm has a bit more of a southerly component which may limit the downslope affect. Anyway, for now we have the advisory from 18z through 12z Wednesday for Pima, Santa Cruz and Cochise counties. The wind will impact fewer locations during the nighttime hours and will be hit and miss. Also, will likely need to extend into Wednesday for eastern areas on later shifts once we see how this plays out. In other words, adjustments are likely. As for precipitation, the trend for southern Arizona continues to see diminished modeled rainfall while central and northern AZ remains the focus. Not really expecting any rainfall today and much of tonight and will need to wait until Wednesday when the front gets closer. Even then it will more than likely be scattered showers rather than a solid area of precipitation. Parts of southeast Cochise county may not even see any rain from this event. As far as snow, the snow level will remain quite high through most of the time it is precipitating with a few inches above 8,000 for the Sky Islands. The high elevations of the White mountains will be closer to the focus of heavier precipitation and should see up to a foot of new snow through this event above about 8-8500 feet. Lastly, this system will bring rather cool air along with it with highs running 10-20 degrees cooler Wednesday and Thursday. Then lingering troughiness across the west will hold temperatures well below climo through the weekend although precipitation should remain to our north. && .AVIATION...Valid through 22/12Z. SCT-BKN clouds 9-13k ft MSL through the period with local MVFR CIGS and mtn obscurations in SCT SHRA north of KAVQ-KSAD-KCFT after 21/18Z becoming NRMS SHRA/ISOLD TSRA aft 22/06Z. S-SW SFC winds increasing to 18-28 kts with gusts 35-45 kts aft 18Z especially south of KGXF- KAVQ-KLSB creating ISOLD BLDU. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A strong storm system will bring strong and gusty winds to the area today through Wednesday and scattered precipitation very late tonight through Wednesday night and possibly into early Thursday. Cooler than normal temperatures will linger through the weekend with the air mass gradually drying out resulting in Min RH levels dipping into the single digits early next week. && .TWC WATCHES/WARNINGS/ADVISORIES... Wind Advisory from 11 AM this morning to 5 AM MST Wednesday for AZZ501>504-507-508-512>515. && $$ Public...Cerniglia Aviation...Drozd Fire Weather....Cerniglia Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
NWS TWC Office Area Forecast Discussion