


Area Forecast Discussion
Issued by NWS Phoenix, AZ
Issued by NWS Phoenix, AZ
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
787 FXUS65 KPSR 141106 AFDPSR Area Forecast Discussion National Weather Service Phoenix AZ 405 AM MST Tue Oct 14 2025 .UPDATE... Updated Aviation && .KEY MESSAGES... - A slight chance for a few light showers exists today across higher terrain areas of south-central Arizona, as well as southeast California. - Dry weather will return to the region the remainder of the week with temperatures primarily remain below normal. && .SHORT TERM /Today through Wednesday/... The final shortwave in a parade of tropically originating features was lifting into NE Arizona early this morning with substantially drier air punching into SW Arizona. In fact, objective analysis depicts a dryline across western Maricopa County with sfc dewpoints in the upper 50s/lower 60s and mixing ratios above 10 g/kg still present in advance of this boundary. Sufficient ascent on the southern periphery of the shortwave along with deep southerly flow pulling moisture over terrain features continues to support isolated showers north and east of Phoenix. This scenario may persist for a few more hours this morning, however loss of ascent mechanisms and increasing advection of dry air aloft should force any remaining shower to mountain peaks heading through the afternoon. The most obvious feature on early morning WV imagery is an intense cold core circulation diving south along the central California coast. The southerly propagation of this vorticity center has just about ceased with excellent confidence this feature pivots inland towards southern NV/UT over the next 48 hours. The pronounced strong cyclonic flow edging into the SW Conus will ensure moisture continues to be scoured away from the area with forecast soundings showing boundary layer mixing ratios falling to around 7-8 g/kg, and total column PWATs under 0.75". Closer to the trough axis in California, a Pacific front will surge onshore today, however shallow moisture should mostly be trapped on the windward side of the coastal range, and only a few elevated showers might survive inland. Midlevel height falls and enhanced winds in the H8-H7 layer will continue to support locally strong, gusty winds near SE California terrain features today, though with the vorticity center beginning to lift away from the region, winds should slowly relax through Wednesday. Otherwise, H5 heights falling into a 570-574dm range and cold advection aloft over the next 48 hours will allow temperatures to cool to 8F-12F below normal by Wednesday. && .LONG TERM /Thursday through Monday/... The core of negative height anomalies will have lifted into the northern Rockies/plains and weakened substantially during the latter half of the week, albeit with positively tilted troughing lingering into the SW Conus. Persistent westerly flow will ensure further moisture erosion throughout the week while H5 heights hovering below 578dm will keep temperatures sequestered 4F-8F below normal, though larger than expected ensemble numerical spread only yields moderate confidence with temperature potentially warming faster than forecast. Nevertheless by the weekend, there is good model agreement that some form of shortwave ridging will build into the SW Conus with H5 heights possibly exceeding 588dm and temperature rebounding into a near normal range. The majority of ensemble output shows the next Pacific trough early next week remaining north of the forecast area before potentially amplifying downstream over the plains (a very La Nina-like pattern). However, enough membership (including the operational GFS) shows vorticity and strong jet energy digging close enough to the CWA to possibly incur strong, gusty winds and reemergence of below normal temperatures. Regardless, there is little to no model evidence of any better moisture source returning, and the prevailing dry weather should continue. && .AVIATION...Updated at 1105Z. South Central Arizona including KPHX, KIWA, KSDL, and KDVT: Winds and the potential for brief cloud decks below 6K ft AGL will be the main weather issues through Wednesday. Winds have been widely variable (SE to SW) this morning, but should settle towards a S/SE direction by mid/late morning. Gusts near 20kt may be common into the afternoon as directions only slow attempt to veer to SW, and a prolonged period of a cross runway component (160v210) appears likely into mid afternoon. Confidence is moderate that cloud decks 5- 7K ft may materialize this morning, though actual cigs may be limited to upslope areas northeast of terminals. Scattered cloud decks will have the tendency to rise through the afternoon before dissipating around sunset. Confidence in the timing of the nocturnal wind shift tonight back to easterly is rather low. Southeast California/Southwest Arizona including KIPL and KBLH: Occasionally gusty winds will be the main weather issue through Wednesday morning under mostly clear skies. Winds will continue to favor a westerly component at KIPL and S/SW at KBLH. Gusts 20-30kt should reemerge this afternoon before relaxing after sunset this evening. && .FIRE WEATHER... Drier air across western districts will completely sweep through the entire region today and Wednesday bringing the start to a prolonged period of more tranquil weather. While minimum humidity levels will only fall into a 30-50% range the next couple days, values will retreat closer to a 20-35% range during the latter half of the week. Overnight recovery will largely be good to excellent above 50%. Locally gusty winds 20-30 mph will be common today, particularly across western districts, however winds will be far weaker the remainder of the week with limited gustiness. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...Wind Advisory until 11 AM PDT this morning for CAZ562. && $$ SHORT TERM...18 LONG TERM...18 AVIATION...18 FIRE WEATHER...18