Severe Weather Discussion for May 11 – 17, 2015.
– Showers and thunderstorms are possible on Wednesday, a few severe thunderstorms are possible. A similar threat is present on Friday.
– Severe thunderstorms are possible Saturday and Sunday across Oklahoma.
– Temperatures will be in the low 70s Monday – Wednesday, upper 70’s Thursday and low 80s Friday – Sunday.
– Severe Thunderstorms: 45%
– Storm Chase: 50%
Upper system current producing severe weather in southern Oklahoma will continue moving northeast into the Great Lakes region by Wednesday. Shortwave ridging will be present across Oklahoma Monday and Tuesday with limited precipitation chances. A weak southern stream shortwave trof will approach the region from Mexico on Wednesday. Moisture will attempt to return ahead of this system but the setup does not appear favorable for severe weather. Wind fields will be marginal and sufficient deep layer moisture. However, the surface features appear to favor showers and thunderstorms more than severe, although a few severe thunderstorms are possible.
Stronger closed low settles into the SW US on Friday and starts eastward towards Oklahoma. This should create a favorable environment for thunderstorms on Friday. Wind fields again are marginal and moisture content remains high given PW values of 1.7. Severe thunderstorms may be more likely on Friday than Wednesday as a lead shortwave trof reaches NW Texas by late afternoon. The greatest chance for any severe thunderstorms will be western Oklahoma.
Upper system moves into the state on Saturday with stronger wind fields approaching the state and a dryline in the eastern Texas panhandle. The closed low/trof has a neutral tilt to it, so not sure how favorable conditions will be for significant severe weather. However, given good wind fields and moisture, CAPE values are in the 2000 J/Kg range and will be sufficient for severe thunderstorms. Saturday may be another case of widespread showers and thunderstorms ahead of the main system, thereby limiting the severe weather threat.
Numbers looks good and didn’t have to make many changes. EC seems a little cool tomorrow and Tuesday, so went with NWS Norman.
OKC Temps 05/04 – 05/10
My Numbers: low 80s, lows 80s, upper 70s, upper 70s, upper 70s, low 80s and low 80s.
NWS Numbers: 80F, upper 70s, mid 70s, upper 70s, upper 70s, upper 70s and upper 70s.
Actual: 81F, 74F, 76F, 77F, 74F, 74F and 80F.