Posts

John Homenuk

High latitude blocking puts Spring on hold

/by

It’s almost too fitting. For much of the winter, meteorologists and hobbyists alike spend countless hours attempting to forecast and predict the likelihood of high latitude blocking development. This year, stratospheric warming events were expected to kick off changes that would eventually lead to the development of said high latitude blocking, and change our pattern to a cold and snowy one. While the pattern turned cold and snowy for sure, the high latitude blocking never came to fruition. In fact, the NAO stayed positive for much of the winters duration.

Well, it’s finally here. Just in time for Spring.

Read more

John Homenuk

Changing pattern could lead to multiple storm threats

/by

We warned you that this was coming. Now, the pattern change is finally beginning to appear on medium and long range model guidance from late December into January. Thanks in part to changes in the stratosphere and retrograding mid and upper level atmospheric features, the pattern over the next week or two will become much more favorable for not only colder than normal air, but winter weather in our area as well. Contrary to what it may seem, the pattern currently is quite unfavorable for cold air and winter weather. Warmer than normal air has settled in to Southern and Central Canada over the past week or so, muting any potential shots of cold air with northwesterly winds.

But the notable feature around the Northern Hemisphere will begin retrograding over the next several days. It begins with the troughiness over the Gulf of Alaska and ridging in the Eastern Pacific. Both of this features will progressively retrograde westward over the next 7-10 days. The end result will bring a mean trough to the Aleutian Islands and a ridge to the West Coast of the United States and British Columbia (also known as a +PNA). Further securing the changing pattern will be the development of a +EPO ridge in Western Canada and the potential for ridging to develop over Eastern Canada, Greenland and the Western Atlantic.

Read more

John Homenuk

PM Update: Winter weather set to impact the area

/0 Comments/by

A strong cold front, which crossed the region earlier today, is ushering in a much colder airmass — and a record breaking arctic airmass to the Central and Western United States. A developing disturbance along the front will touch off more precipitation in our area later this evening into Saturday. The dramatic cold front has not yet delivered arctic air to the East Coast, but the arctic gates have opened over much of the Midwest, Northwest and North-Central United States.

Some fascinating numbers evidencing the strength of the cold front include:

1) A minimum temperature reading of 28 degrees in NW Mississippi, and a maximum temperature reading of 84 degrees in SE Mississippi.

2) Temperatures in the upper single digits and lower teens as far south as Oklahoma, Texas, and Arkansas, where several inches of snow has fallen.

3) A minimum temperature reading of -23 degrees in Montana, and a maximum temperature reading of 87 degrees in Florida. A 110-degree temperature gradient across the country!

RAP analysis on Friday evening, showing a dramatic cold front over the Eastern US and an arctic airmass over the Central and Western US.

RAP analysis on Friday evening, showing a dramatic cold front over the Eastern US and an arctic airmass over the Central and Western US.

Read more

John Homenuk

PM Update: Much cooler air filtering in

/0 Comments/by

Behind a major cold front, which moved through very early this morning, westerly winds began on Monday. Winds picked up considerably on Monday afternoon, but the air remained relatively warm. Temperatures in the mid levels if the atmosphere remaining somewhat warm allowed for the highs to reach into the mid 60s — making for a pleasant, comfortable late-autumn afternoon. But the airmass is changing rapidly behind the aforementioned cold front.

The low pressure system which helped drag the cold front through the area deepened below 967 hPa in Southeast Canada on Monday, and much colder air will surge eastward to the south of it. Temperatures will plummet into the 20s and 30s overnight on Monday evening into Tuesday morning throughout the area — especially over the interior. Pleasant weather is expected to continue through mid-week with near seasonal temperatures.

Forecast low temperatures on Tuesday morning, from the HRRR model.

Forecast low temperatures on Tuesday morning, from the HRRR model.

Read more