Outlook (Thursday-Sunday)

Generally quiet weather has returned to the state and that will remain the case through the upcoming weekend.

A deep upper level trough of low pressure over the Mississippi Valley will shift eastward and high pressure will build into the western U.S. over the next several days. Northwesterly flow aloft diving from southern Canada into the eastern U.S. trough will allow several shots of cold air to spread southeast, but these should lead to only glancing blows to Oklahoma.

It will be cool tonight in Oklahoma as temperatures drop into the 20′s, but that is near normal for January 31st.  We will make a run up into the 50′s on Thursday before an afternoon cold front shifts winds to the northeast and puts a halt on our warmup.  Thursday night should see the coldest temperatures of the next few days with a low around 20 degrees expected in Okarche.

Winds will become southerly on Friday before yet another front slides through by Saturday morning.  The air behind this front doesn’t look as cold, and overnight lows will be near normal through the weekend with afternoon highs reaching as much as 10 degrees above normal.

The atmosphere will remain dry, and except for a slight chance of showers in southeast Oklahoma on Saturday, no precipitation is expected.

Severe thunderstorms possible tonight…

A high amplitude upper trough over the western U.S. will progress eastward over the next couple of days bringing significant weather changes to Oklahoma.

An unseasonably warm and moist atmosphere is in place across the state this afternoon with most temperatures in the 70′s while dewpoints are in the 50′s and 60′s. Some observed temperatures in southwest Oklahoma are pushing 80 degrees.     In Okarche, the high temperature so far today has been 74 degrees.  This is just two degrees short of tying the record for the date.  The morning low was 53 degrees… which is two degrees above the average HIGH temperature.  The average low temperature for today is 29 degrees.

Strong mid-level flow currently spreading from southeast Arizona northeastward through New Mexico will begin to spread over the central and southern Plains by Midnight tonight.  Coupled with an increasing low-level jet, shear profiles are expected to become favorable for organized thunderstorm activity. A modest amount of instability will remain in place through the overnight hours leading to some of the storms becoming severe. Storms that form late tonight and early Tuesday morning will continue to organize as they spread toward the Mississippi Valley, where a significant outbreak of severe thunderstorms is expected during the day Tuesday.

This afternoon, low pressure is located in northeast Colorado with a front extending eastward along the Kansas/Nebraska border.    Temperatures in Kansas are in the 70′s with temperatures in Nebraska ranging from the low 30′s in the west to upper 40′s in the southeast.  A dryline extends from near the front in northern Kansas to just east of Russell to east of Gage to east of Childress.  The cold front will begin to move south toward Oklahoma by late this evening.  By Noon on Tuesday, the cold front will be catching up to the dryline in northwest Oklahoma and will start moving southeastward through the state.  While thunderstorm activity will have cleared through southeast Oklahoma by late in the afternoon on Tuesday, the actual cold front won’t clear the state until close to Midnight on Wednesday.

Initial thunderstorm development tonight may be displaced a little east of the surface dryline – near the western edge of the deepest moisture and greatest instability. The best guess is for first storms to form in northwest Texas near Quanah and Guthrie.  This is likely to occur in the 1 AM to 3 AM time frame.  Rapid development northeastward to near and just west of Oklahoma City and to near Ponca City will occur shortly thereafter. The strongest storms will be capable of producing some large hail and damaging winds.  As shear steadily increases, there will be a risk of rotating storms, and an isolated tornado is not out of the question.

For a time Tuesday / generally late-morning to late-afternoon / there may be an enhanced risk of wildfires in southwest Oklahoma.  This would be south of the cold front and west of the dryline where the humidity will drop into the teens percent with west southwest winds gusting to between 30 and 35 MPH.

Finally, much colder air will filter into the state on Wednesday and by Wednesday night, temperatures are likely to drop into the low 20′s across the northwest third of the state.

Above normal temperatures / severe storms in Eastern Oklahoma on Tuesday

While the evolution of the approaching storm system hasn’t exactly followed the model trends of over a week ago, it is worth noting that a strong storm will be moving through the central U.S. on Tuesday (29th).  Evidence of this system was showing up on some medium range models as much as 14 days in advance. 

A strong high amplitude trough is located over the far western U.S. this morning.  As strong southwest mid-level flow overspreads the Plains on Monday, a deep surface low will organize near the Colorado/Kansas border.  South winds will continue to return low level moisture northward through the central and southern Plains as well as the central and lower Mississippi Valley. 

Monday will be a very nice day across Oklahoma with afternoon high temperatures expected to reach well into the 70’s in most areas.

A cold front will start to move southeastward on Tuesday morning, reaching the Enid and Elk City areas just after sunrise.  Temperatures will still be well above normal across the central and eastern part of the state.  Most model solutions support thunderstorm development in advance of the cold front across central Oklahoma during the morning hours.  These storms will rapidly expand northeastward and southward by Noon.  It is also expected that the activity will become better organized and severe as it moves toward the Mississippi Valley during the afternoon and evening on Tuesday.  There will be the potential for widespread wind damage with the storms, and a few tornadoes as well.  The severe threat will extend into the eastern U.S. on Wednesday. 

Much colder area will spill into Oklahoma behind the front on Tuesday, and a few snow flurries will not be out of the question Tuesday evening.  Wednesday and Thursday stand to be quite cold before things start to moderate by the weekend.

The spring side of the system was something anticipated several days ago.  The winter side of the storm is the side that is going to be disappointing.  While an area of snow is likely to fall from northeast Colorado to Minnesota, blizzard conditions won’t develop.

Major storm may pay visit to the Plains late this month…

It is quite rare to speculate on the weather nine days out.  I don’t think I’ve ever done it before, and should it fail miserably, I probably won’t be doing it again.  A few days ago, I wrote about the two peak periods of snowfall in Okarche, and commented on the fact that the medium range models were suggesting snow around 29 January.  That just happened to be the start of the second peak period.

The only reason I mentioned that then was because the models were displaying an incredible amount of consistency in the timing of the upcoming powerful system.  Now, a few days later, they still have had amazing consistency with regard to timing and the strength of the predicted storm.  The track forecast has bounced around a little bit, ranging from the Red River Valley to northern Kansas.  Most of the solutions have centered on an intense cyclone moving out of the northern Texas panhandle, racing northeastward toward the Great Lakes. 

The sad part about the current predicted path is that much of Oklahoma would likely remain dry with strong winds, varying temperatures, and blowing dust – with snow remaining to our north and storms to the southeast.  A track farther south would introduce snow to the forecast, and a track to the north would introduce more rainfall.

Because we are talking about a storm nine days out, confidence associated with the current model solutions is low, but higher than what would usually be found.  A worst case scenario would include fierce blizzard conditions in the Plains and Midwest, while sufficient shear and instability could result in a severe weather outbreak for the middle and lower Mississippi Valley. 

At least it is something to look at in the days to come, instead of just the boring, dry cold frontal passages every few days.

Where’s the snow?

It seems to be a common question while rolling through the month of January, but how unusual is a middle of January without snowfall? Not very after looking back at 20 years worth of data.

In Okarche, there are two peaks of snowfall. The first extends from December 24th until January 4th. In this peak period, snow tops out at about 30% of the years of record. It was during this period that we have seen our only accumulating snowfall this season.

A second peak occurs from January 29th until February 10th. During this period, snow tops out at about 40% of the years of record. Our last significant snows occurred during this time frame. 7.1 inches of snow fell on February 1st, 2011, with 4.8 inches falling on February 9th of that year.

The latest medium range global models do not indicate snow in the near future. They do, however, show a major storm moving through the Plains on – January 29th of all things. Time will tell…

Accumulating snow possible in Oklahoma today.

Satellite imagery this morning shows a strong storm system moving eastward across northern Mexico.  Lifting associated with this storm is beginning to spread into southwest Texas.  The system will begin to move northeastward later today and move across the state late this afternoon and tonight.

At the surface, a cold front extends from just east of Muskogee to just east of Ardmore.  Very cold air has moved into the panhandle where 18 degree temperatures are found in Cimarron County.  At 6 A.M., the freezing line has progressed southeastward through northwest Oklahoma.  Deepening cold air will move south and east today, and the Oklahoma City area can expect to see the temperature drop below freezing by sunset. 

While moisture is somewhat limited, models are in agreement that precipitation will be generated by the strong lifting associated with the upper system.  In northwest Oklahoma, any precipitation will fall as snow.  Much of central, northeast, and east central Oklahoma will see a mix of precipitation… starting as rain, changing to freezing rain or sleet, and eventually snow.  While amounts are expected to be light, travel in these areas could become hazardous in spots. 

The SPC SREF is a preferred model early this morning as it appears to be a consensus of operational model data.  Across north central Oklahoma, snow is expected to become a little heavier as a more organized band of snow develops after cold air has deepened sufficiently for snow production.  In this area, snow amounts of 1 to 2 inches appear likely, with 3 inches not out of the question in isolated areas.

Precipitation and upcoming warm weather…

A few light showers remain across central and northeast Oklahoma this evening, associated with the upper low that is moving northeastward out of the state.  Forecast rain amounts for the past 48 hours were trended downward, but could have been dropped further.  In the end, 0.31 of an inch was recorded at Okarche.  Lesser amounts fell to the northeast across north central Oklahoma.  Amounts across the remainder of the state were generally in the ½ to 1 ¼ inch range.  Areas around Durant saw nearly two inches of rain.

A deep surface low will develop in Nebraska on Friday.  With the associated front still to the west of the main body of Oklahoma, we will find ourselves with strong south southwest winds most of the day.  This will result in temperatures coming close to record highs / or about 15 degrees above normal /.

 

 

 

 

 

 

 

 

 

Forecast rainfall adjusted downward…

The upper level low located southwest of Del Rio, Texas this morning is moving very slowly to the east, but has begun to make the turn to the northeast.  This is a slower evolution than what was expected 48 hours ago and has resulted in a delay of the onset of precipitation across most of the state.  The exception has been southeast Oklahoma where precipitation amounts have already exceeded one inch in some areas. 

Many areas of southern, central, and eastern Texas have seen rainfall amounts of three inches plus, while portions of Louisiana have seen in excess of five inches. 

The upper low will begin to lift rapidly northeastward over the next 12 hours.  As a result, rainfall will make a surge northward into the state by late afternoon. 

The combination of a delayed start to precipitation and the rapid movement of the system to the northeast have caused forecast rainfall amounts to be shifted downward.  An additional one to two inches may fall over southeast Oklahoma, bringing total amounts to near three inches in some areas.  Otherwise, amounts near one inch will be seen generally south of I-40, with amounts around ½ inch north of I-40.

 

Rain chances increase by midweek…

A strong upper storm system is located over southern California and southwest Arizona this morning.  The system will continue to dig southeastward into northwest Mexico by daybreak on Tuesday… then slide eastward toward the Big Bend area of Texas by Wednesday morning.  By Thursday morning, the strong, compact system will be located over Oklahoma moving quickly northeastward.

Widespread showers and thunderstorms will begin to break out in Texas during the morning hours of Tuesday.  This activity will spread northward into Oklahoma during the early morning hours of Wednesday… and across all of the state by late in the day.  Sufficient moisture and lifting will likely lead to a prolonged period of showers and thunderstorms over southern Oklahoma.  As the system rapidly ejects northeastward, areas of central and northern Oklahoma will be seeing precipitation for a shorter duration.  While beneficial rainfall is likely to fall across all of the state… amounts will be greater in the south with lower totals expected the farther north you go.

In addition to the rain, elevated instability will lead to thunder… generally from I-40 south.  These embedded thunderstorms will locally enhance rainfall amounts.

In somewhat of a surprise for early January, the air mass will not be sufficiently cold enough for accumulating snow out of this system.  The temperature profile even in the coldest core of the low will be warming as the system ejects northeast.