April 21 Morning Forecast

Low clouds were moving into northern OK around the time of the weather briefing this morning (14Z) with SREF forecasts indicating some light rain/showers likely between 15-18Z time-frame over northcentral OK. Some light rain and showers will likely persist through the afternoon before moving off north/east. The 850mb level moisture and southerly jet will keep this going as there is not much upper-level forcing in the area.

A surface front over north/central Texas will begin to lift this afternoon. As the warm front reaches near the OK/TX border later increased chances of severe storms are forecast.

Friday a surface cold front is expected to move through our area as the associated low pressure progresses eastward across the high plains. This front is forecast to move through north-central OK around 18Z and down into central ok by 21Z. Afternoon convective initation is likely along this line 20-22Z from central into NE OK. These linear storms will fire up likely too far south and east of the SGP CF,  but could affect the Norman/Purcell area. CAPE values are also forecast to be rather strong ahead of the front ~21Z so these storms would likely go severe.

The surface front will continue to push through early Saturday morning before stalling out over southern OK, into northern TX. Convection again will be likely along the frontal boundary Saturday afternoon into evening. The models have been wobbling the frontal position back and forth across OK, so chances of storms remain but it appears to remain too far south of the SGP region.

A stronger upper level system wave will approach the southern plains Sunday into Monday, and along with the return of moisture, possibly the front lifting back north/west, Sunday appears to be a good chance of widespread precipitation over the region during the afternoon into evening time-frame. Severe storms may be possible again Monday as the upper storm kicks through, but will have to wait until later to determine where the surface features will line up at.