Severe Weather Discussion for February 14 – 20, 2011.
– Chance of rain Saturday and Sunday, isolated thunderstorms are also possible.
– Temperatures will be in the low 60s Monday – Tuesday, upper 60s Wednesday, mid 70s Thursday, mid 60s Friday, near 60 Saturday and Sunday.
– Fire danger will likely be extreme on Thursday, very high Wednesday and Friday.
– Severe Thunderstorms in Oklahoma: 5%
– Storm Chase: < 5%
– Winter Precip: < 5%
Mid-level flow has flattened out the past few days with short-wave ridging occurring early in the week. This will quickly give way to southwest flow as a western U.S. trof moves onshore. Models are struggling with this system, but generally develop split flow with this system as the northern jet remains in Canada. ECMWF and to some extend the GFS bring the system out in pieces, but even this seems to vary from run to run. What seems obvious this week is well above normal temperatures almost all week.
One shortwave trof moves quickly northeast across KS/NE on Thursday. It induces a lee surface low, which strengthens southerly winds across Oklahoma. Gulf moisture is expected to return ahead of this system but will be sent east by the dryline. Hot and dry conditions are likely behind the dryline, which should make for a problematic fire day in western Oklahoma. Upper system moves by and a weak wind shifts moves into the state. Temperatures will drop some, but not much. Model differ if a stronger front moves into the area on Saturday with the ECMWF being more intense with the front. However, it also shifts the high east quickly allowing for warmer temperatures on Sunday. I split the difference. Moisture should be lurking nearby and rain is possible across the area. The GFS wants to bring a stronger system out just beyond this forecast period, but confidence is low. The weather should be quite pleasant this week and not all that unusual for late winter.
Went above 12z MOS much of the week and split the difference on Saturday between the GFS/ECMWF.by