Storms Tonight, Some Severe

What a day!  Notice the maximum winds recorded across the state as of late this afternoon and keep in mind those are straight line winds associated with the extreme pressure gradient and are not related to any storms.  At least not yet as storms are in the forecast for tonight.  More about that in a moment.

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Notice the strongest winds have so far been out in the panhandle and that is also where the humidity values are the lowest as you can see on the relative humidity map as of late this afternoon.  That extremely dry air will be surging eastward tonight as a dry line/cold front moves on across the state. 

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It should be out of the state by sunrise, but along and ahead of the actual frontal boundary there will be a good chance of showers and storms, some of which will be severe.

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The primary threat looks to be wind and hail, but isolated tornadoes cannot be ruled out as the system sweeps across the state tonight.  We certainly do need the rainfall, but this will be a rapidly moving system which will limit the rainfall amounts to around ¼” for most locations but with locally higher amounts possible.  Certainly not a drought breaker and after the high fire danger of the last few days, it will not be long till fire danger concerns return once again.

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By morning, everything will have moved on eastward and we will have clear or clearing skies, a brisk NW wind, and temperatures in the upper 30s to mid 40s from N-S across the area.  Sunny skies will be the general rule all day and our NW winds will become more W during the afternoon hours as the surface high pressure ridge drops on south of us.  As a result, look for afternoon temperatures to make it into the mid-upper 60s which is still well above normal.  Normal values for this time of year are 59/37 and so far today has been 78/58 as a frame of reference.

The winds will be calming down for Tuesday night and with clear skies, temperatures should be dropping into the 30s to start the day Wednesday.  That means some frost potential and the more outlying, rural locations could see a light freeze.  Sunny skies and a return to southerly winds should get us back into the lower 70s that afternoon, so quite a diurnal range.

As you can see on our forecast page, we could see a few showers again along about Thursday, another chance of showers or storms for the early part of the weekend and again going into next week.  This is all due to a very fast W-E jet stream which is located from well out in the Pacific and punching across the lower 48.  Notice the map as of Noon today which is at the 500 mb or 18,000’ level and in which the colors represent the strongest winds at that level. 

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This extremely fast jet stream basically moving right over OK brings systems through very quickly but the W-E flow is keeping the really cold air bottled up well to the north and therefore we remain very mild even after a front moves through.  Also, this extremely fast jet stream over us makes it difficult for any one particular system to tap into much moisture and as a result we get scattered showers/storms which move very quickly and have very little impact on our drought situation.  However, this very strong jet stream also means the dynamics at the surface and aloft are quite strong so that what storms do develop will have severe potential and that will be the case throughout this forecast cycle.

Bottom line is a continuation of the very mild conditions that have dominated our weather since early January and will likely persist over the foreseeable future.  Temperatures are expected to average above normal over the next two weeks along with only scattered chances of showers/storms during that time frame.

So, stay tuned and check back for updates.

Dick Faurot