Good Friday Morning Bloggers,

If you have wondered if there is a difference from last October to this October let me end the discussion with this:

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This forecast rainfall map above shows the total precipitation for the next 300 hours ending October 25th. Near Kansas City most of that 1″ of rain comes from this weekends chance of showers and thunderstorms. The big difference that is rather telling is out west where they are dealing with a major fire disaster that is ongoing.  Look at San Fransisco east to Lake Tahoe in the Sierra Nevada mountains.  Most of that region is not forecast to even have 0.01″ of total precipitation during this rather critical time frame.  Last October, South Lake Tahoe had 5.04″ of liquid from a series of very wet storm systems that blasted California from October 14th to 18th. This then returned in December, February, and April.  That early series of storms was good news for that reason, and bad news as well. The good news is that the drought got obliterated in the next few months.  The bad news is that there was significant flooding.  This year the bad news is that the fire disaster is ongoing and there is no rain in sight. This is a huge difference from last years pattern to this year. One of many huge differences. According to the LRC a unique pattern is setting up right before our eyes. We are around one week into this pattern, so let’s hang on for a few more weeks before we make any conclusions, but the first evidence is in out west.

This weekends set up:

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This forecast map above shows the surface forecast valid at 10 PM Saturday night. A low pressure area is forecast to be in northern Illinois with a cold front trailing southwest to just southeast of KC by this time frame.  A line of thunderstorms is likely with some severe thunderstorm producing a main threat of damaging winds and large hail. The SPC doesn’t even mention tornadoes, but it is still something to monitor closely.  Look at what happens to this storm system by Sunday evening. Snow is forecast to fall in Canada while a weak line of showers and thunderstorms tracks across New York trailing southwest to Alabama. West of this are it is completely dry all the way to the Pacific Ocean.

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Severe weather risks:

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The risk is below slight today, and then there is a this slight risk of severe thunderstorms tomorrow from northwest Illinois southwest to southeastern Kansas.

From the SPC:  Thunderstorm development with a threat for isolated large hail and wind damage will be possible from the southern High Plains into the Midwest Saturday afternoon and evening.  A strong short-wave trough is expected to progress across the northern/central Rockies into the High Plains by 7 PM Saturday as 500 mb flow increases downstream across Nebraska/Iowa/southern Minnesota.  While this feature will lag the delineated severe risk corridor somewhate, a synoptic front should stall across the central Plains/mid Missouri Valley region Friday and will serve as the focus for convection by mid-late afternoon.  Latest short-range guidance suggests a narrow zone of strong boundary-layer heating will be noted from the Texas Panhandle northwest across south-central KS into northern MO and southeast IA.  Forecast soundings suggest surface parcels will reach their convective temperatures around 4 PM to 5 PM and frontal ascent should encourage thunderstorm development along the wind shift, especially by early evening as the front begins to surge southeast.  High precipitable water values, in excess of 1.5″, will not prove conducive for steep mid-level lapse rates but low-level heating is expected to aid buoyancy and a robust squall line should evolve with a strongly sheared environment. Wind damage and some hail are the primary threats, especially across Kansas/Missouri into southeast Iowa as adequate buoyancy will extend into this region where large-scale forcing for ascent will be greatest. While short-wave trough will only glance the southern High Plains, some severe threat should extend into the Texas Panhandle where low-levle lapse rates will be steeper than northern latitudes.

There is also a chance that a few thunderstorms will form over northern Missouri this evening near the front. There is some capping today, but temperatures and humidity are rising.  We will be monitoring these developments closely on 41 Action News.

Thank you for spending a few minutes reading the Action Weather Blog featuring the Weather2020 and the cycling weather pattern. Go over to the blog on Weather2020 and join in the conversation and let us know if you have any questions.

Gary