Quiet conditions at the moment across the AMA forecast area. A cluster of storms that was over the northeast portion of the region has recently pushed off to the east. Minimal cloud cover remains, although there is a small CU field left in the vicinity of outflow from the previous storms. Instability is steadily building across the region with AllSkyLAP CAPE values from 2000-2500 J/kg in many areas. An ongoing 18Z balloon launch from AMA still shows a weak cap around 770 mb, but this should be overcome later this afternoon as diurnal instability increases. Guidance suggests instability will peak later today near 3500 J/kg. Lapse rates are also very steep, with 700-500mb lapse rates near 9 C/km. An upper-level impulse tracking through the area today will increase bulk shear values to around 40 kts. The surface dryline, which currently lies just west of the forecast area, should advance east into the area later this afternoon.
Expect severe storms to develop along/ahead of the advancing dryline within the next 1-2 hours. The moderately strong instability, steep lapse rates, and moderate shear support large hail with the initial development. The storms should eventually grow upscale into a line and more of a damaging wind threat.
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| 19Z Surface Plot/1929Z Visible image |
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| 1828Z AllSkyLAP CAPE |
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| 18Z AMA RAOB - CAPE values comparable to AllSkyLAP |
Alex Brown
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