…Active weather week in store for Oklahoma…
Models are in reasonably good agreement concerning the weather across the state Monday through Wednesday.
An upper level low pressure area just off the coast of the Pacific Northwest will dig southeastward, reaching the Central Rockies by Wednesday. There will be moderate west southwest mid-level flow over the Plains on Monday and Tuesday. On Wednesday, flow will sharply increase as phasing jet segments associated with the Central Rockies low spread northeastward across Texas, Oklahoma and Kansas.
Moisture is plentiful from Texas to the Lower Mississippi Valley this Sunday evening, with precipitable water values approaching 2 inches over southeast Texas. Slugs of very moist air will continue to flow northward across the eastern 2/3s of the state – to the east of a dryline – through Wednesday.
Extensive cloud cover and light precipitation has kept temperatures well below forecast values over the eastern half of the state today (Sunday). So much so, that temperatures will actually be warming overnight with lows Monday morning higher than some highs on Sunday.
On Monday, low pressure will be organizing near the Kansas/Colorado border. A dryline will progress eastward during the day, reaching almost to the Highway 81 corridor by late afternoon. As this occurs, very warm and dry air will spread across western Oklahoma and the Panhandle on gusty southwest winds. Fire danger will be very high west of the dryline. East of the dryline, temperatures will be mild or warm, and it will be quite moist. Strong capping is expected to limit the threat of thunderstorm development along the dryline.
A weak mid-level impulse will get the surface low moving east across Kansas on Tuesday. As this occurs, a cold front will be moving southward and approach the Kansas/Oklahoma border before becoming nearly stationary. After an overnight retreat, the dryline will push farther into Oklahoma and extend from near Ponca City to near Lawton by late afternoon. Fire danger will once again be elevated west of the dryline. Thunderstorms will be possible near the front over southeast Kansas and adjacent areas of Oklahoma. There are some indications that the cap may be breached in a couple of spots along the dryline near the I-35 corridor. If this occurs, rapid severe thunderstorm development would be possible. Any storms that do form would be isolated, and no broad areas of precipitation are expected. Given the degree of instability and shear – should storms form – they would be capable of becoming supercell in nature with all facets of severe weather possible. By late Tuesday, surface pressures will begin falling over eastern Colorado and western Kansas in advance of the approaching upper storm system.
On Wednesday, a deep surface cyclone will be found near the Kansas/Colorado border. The dryline which will have had retreated overnight will make a quick advance eastward, reaching the Highway 81 corridor by afternoon. This will be in response to a strong jet segment ejecting from the base of the Central Rockies upper low. The atmosphere east of the dryline will be moist and highly unstable with MLCAPE expected to reach values of 2500 to 3000 j/kg. 500 mb winds approaching 70 knots will be overspreading a 40 to 50 knot low level jet. Forecast soundings show wind profiles very supportive of supercell storms. Forecast hodographs show impressive low level turning. Rapid development of supercell storms will be possible by mid to late afternoon. The most favored area will be along the dryline north of I-40, but isolated storms will also be possible to the Red River. Storms that form will be capable of producing very large hail and damaging winds, along with tornadoes – some possibly strong.
The dryline is expected to retreat through western Oklahoma, before making another surge eastward during the overnight hours into Thursday morning. The redevelopment of severe storms will certainly be a possibility as this occurs.
Fire danger will be very high to extreme over western Oklahoma and the Panhandle – behind the dryline – Monday through Wednesday.
An isolated severe storm will be possible across central and eastern Oklahoma, Tuesday afternoon and evening.
More widespread severe storms are expected across central and eastern Oklahoma, Wednesday afternoon and through the overnight hours into Thursday.
Monday morning: 54
Tuesday morning: 62
Tuesday: 89 / Slight chance of showers and thunderstorms
Wednesday morning: 64 / Slight chance of showers and thunderstorms
Wednesday: 85 / Showers and thunderstorms possible
…PRECIPITATION CHANCES THROUGH WEDNESDAY…
CHANCE OF 0.01 INCH – 90%
CHANCE OF 0.10 INCH – 90%
CHANCE OF 0.50 INCH – 50%
CHANCE OF 1.00 INCH – 20%
CHANCE OF 2.00 INCH – 10%
CHANCE OF 3.00 INCH – 5%