The various model runs were quite good forecasting the strong outflows over far southeastern AZ and SW NM where there was a terrible accident where the freeway crosses the Lordsburg Playa. I was driving back from Paradise on I-10 shortly after the dust storm and at that point, the freeway had been closed. It was spooky driving on an empty I-10 except for occasional tow trucks and emergency vehicles going the other way towards NM. WRF-GFS was the best and is below.
Initialization/Discussion
The WRF runs are not all configured for the summer convective season yet and may have some issues with forecasting convection correctly. Most runs will be transitioned over the next few days.
Southern NM was very active last evening which resulted in debris clouds advecting in over southern Arizona. The key for today is if these clouds will thin out enough to allow sufficient heating for afternoon convection as IPW has increased to 26mm at Tucson. Unfortunately, far SE AZ and far SW NM do not have any functioning GPSMET IPW stations so it's hard to say what is immediately upstream from us. Demming is 28mm so southern NM is wet.
Of course, the first day back is tough as no model run has enough clouds; even the one that uses the new setting that is supposed to improve cloud coverage. Because of overnight warmth, we got a head start on heating so, in spite of clouds, we're pretty close to the models.
Looking at upper level maps, there does seem to be a weak inverted trough between Tucson and El Paso which is either a leftover MCV or an inverted trough. In any case, this trough should help organize convection. The 12Z NAM has a fairly sharp 500mb trough located just south of Douglas which looks OK. The 6Z GFS is similar. The 6Z WRFGFS also had the best cloud coverage of the morning models, but still not enough. Model confidence is quite high as the clouds over SC Arizona are burning off quick enough to not be a big factor.
Day 1
Moisture continues to slowly increase over eastern Pima and Santa Cruz during the morning hours and is more than enough for deep convection.
CAPE is also very high for this time of year in SE Arizona with some values exceeding 2500 J/Kg. NM also have very high CAPE.
Deep convection forms over the high terrain of Santa Cruz County by early afternoon.
As mentioned by Dan Henz this morning, the mixed/sub cloud layer is very deep, extending to nearly 500mb. The lower/mid level wind profile is also very good with mid-level easterlies and low-level northwest winds. CAPE is low in the Tucson area but may be enough to support storms even in the lower elevations.
Storms are present over eastern Pima County later this afternoon while storms over the White mountains are just getting started.
Winds are going to be very strong with gusts above 50 knots in eastern Pima County with these storms. It appears storms will put the break on temperatures so perhaps Tucson won't have record highs.
The rest of SE Arizona becomes very active by late afternoon as outflows converge across Cochise County, triggering new development. The big story is the winds as it looks like a repeat of yesterday with very strong outflow winds.
A few storms form in far eastern Pinal County and eject outflows into the Phoenix area this evening accompied by a dust storm. Strong winds continue over SE Arizona.
Due to slightly cooler/wetter air, it looks like Phoenix won't make it to the 'magic' 120 mark. It's going to be close and maybe KLUF can do it.
Looks like the outflows provide some cooling for Phoenix this evening.
A Day 2 update will follow later this morning.
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