Saturday, June 24, 2017

Low-Level Moisture From The East This Weekend

Debris cloud providing sunrise color again this morning.

Surface chart below is from NCAR at about 07:30 am MST - note higher dewpoints to the east and the strong east-northeast winds, especially over west Texas. Pressure gradient from New Mexico/Texas border over to Tucson is quite strong, with pressure to our east more than 10 mb higher.

The morning TWC sounding plot above indicates two old BL residual layers aloft that reach above 500 mb, with generally westerly winds. The 500 mb temperatures are quite cold wrt the forecast high today of 113 F. Thus, there should be some mountain buildups closer to the metro area today.

The sounding forecast below is from Atmo's WRF-GFS run at 06 UTC. The sounding exhibits a single, well-mixed BL that yields convective cloud bases around 500 mb, with only about 4-5 g/kg mixing ratio in the sub-cloud  layer. The forecast sounding is quite classic for dry microbursts, if light showers develop over the mountains.

The model continues to forecast widespread thunderstorms over southwestern New Mexico this evening - composite radar echoes above are valid at 07:00 pm. The PW forecast below, valid at 10:00 pm, indicates outflows bringing considerably higher PW into southeast Arizona, so that tomorrow could be an interesting storm day.

1 comment:

  1. Hazy last week or more: earlier high capping dry, smoke-filled heat. Now, easterly moisture wedged under the high...seeing no evidence all their storms forecast today will emerge. My guess is it's all capped, but hopefully I'm wrong and we get some rain-cooled air which helps NM, though this is still early for monsoonal flow.

    But we almost hit our all-time record, depending where that record was made...110F is the official highest-ever, the airport at 108 and NMSU at 111. Close enough!