It was the most active day of the year as widespread storms moved across both Tucson and Phoenix. The strongest thunderstorms were east and west of Tucson. The 12Z forecasts were pretty good in and around Tucson but didn't have enough activity from Phoenix and to the north. The 15Z WRFRR did have storms for Phoenix, but not enough. I also ran the WRF using the ESRL RRv4, and this performed the best of all the initializations. I'm going to replace the early WRFGFS with this initialization for the rest of the season to see how things go.
There was a lot of lightning! Most of what I saw personally was either IC/CC or obscured by rain.
Initializations
The inverted trough that was partially responsible for the active day is still in the neighborhood as it's located from around southern Arizona, down into NW Mexico. There are a couple of MCVs located over far SE Arizona and SW NM. There are widespread clouds associated with the Arizona MCV. The MCVs and clouds were not initialized well, but both the NAM and RR do have an area of cyclonic circulation in far northern Sonora. These errors will result in too much heating and too much convection for that area. PW errors are generally small except for the NAM which is somewhat too wet in Mexico. The RR is the favored initialization, and the WRFRR should perform well except for southeastern Arizona.
As mentioned yesterday, the day after a big event is typically suppressed, and that is the case today. The Tucson 12Z sounding displays the green "onion" T/Td profile with a cooler and drier lower troposphere.
A weak surge continues to import moisture into southern Arizona, so that is at least a plus.
All the cooling and slight drying results in much less CAPE. It looks like only the high country around Flagstaff has a decent shot for storms today.
Day 2
Slight drying continues in spite of a continuing weak surge. The atmosphere does recover, and there is a moderate to high amounts of CAPE forecast for the afternoon hours over parts of southern and central Arizona.
Mid-level steering is quite good as the 500mb high center becomes consolidated over southern CA. Some cooler air is also located over eastern Arizona, so it's looking like a more active day with the possibility of some storms moving into the lower elevations.
In spite of a better-looking setup, not too much happens tomorrow.
Unfortunately, the mixed layer isn't very deep and has a significant cap. Too bad as everything else looks good.
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