Omega Block Pattern Major Influencer of Weather in Days Ahead

What is known in meteorological terms as an Omega block pattern is going to lead to torrential rain over the Plains and the Northeast in the days ahead. What is this atmospheric element and how does it work to produce so much rain? Read on for all of the details.

Understanding the Omega Block Pattern

An Omega blocking pattern happens when the jet stream forms a shape reminiscent of the Greek letter Omega. The pattern delivers what is essentially a ridge of high pressure located between two areas of low pressure. This movement slows down the usual west-to-east movement of weather systems.

The blocking of the systems translates to weather that stalls out over a particular region. Depending on the location and the strength of the block, the end result could be extended periods of hot or cold temperatures as well as wet weather.

In general terms, the slow-moving areas of low pressure tend to set up to the west and the east of the Omega block. This translates to an extended period of unsettled conditions to the east of each zone of low pressure. Conversely, the northern half of the block generally enjoys dry and sunny conditions with temperatures that trend warmer than usual.

How the Upcoming Omega Block Will Influence the Weather

The upcoming Omega block pattern is expected to result in heavy rain over a good part of the Plains and the Northeast. Temperatures will also fluctuate greatly within the blocking pattern.

The forecast is calling for several days of torrential rain beginning Sunday and lasting through at least Wednesday across the central, southern, and High Plains. The moisture is good news for the parts of the High Plains that have been under growing drought conditions as of late.

However, the influx of moisture could spell trouble for parts of Oklahoma and northern Texas that have seen too much rain lately. This region notched a record wet April, swelling waterways and creating a higher chance of river flooding with each round of repeated moisture.

Lubbock, Texas, will be one of the first areas to see the arrival of the unsettled weather. This part of the High Plains is forecast to see the chance of rain increase later in the day on Sunday and into the overnight hours. Winds will also increase at the end of the weekend, reaching speeds of 20 to 30 mph from the south-southeast. Monday is setting up to be the stormiest day of this pattern. The overnight forecast is calling for 1 to 2 inches of rain.

Heading to the eastern U.S., multiple rounds of locally heavy rain are in store for the mid-Atlantic and the Northeast. This includes the busy Interstate 95 corridor cities of Washington, D.C., Philadelphia, and New York City.

For instance, New York City will experience building clouds and the chance of rain by Sunday afternoon. The Big Apple is expecting about a quarter of an inch of rain overnight Sunday and into Monday. It will be even rainier on Monday with rainfall amounts of about a half of an inch on tap for the daytime hours and another half of an inch expected under the cover of darkness. Cooler temperatures will come along with the rain with highs remaining in the mid to upper 60s.

A large part of the East Coast is also experiencing varying levels of dry or drought conditions. The surge of precipitation will help to alleviate these concerns, however, it will also come with the added concern of flash flooding if the rain comes down too hard and too quickly. Urban areas and hilly terrain will be the most at risk of flooding.

Roller Coaster of Temperatures

The persistent plume of moisture will not be the only impact of the Omega blocking pattern. Temperatures will also bounce around at this time.

The northern half of the U.S. from the Pacific Northwest and over into the northern Plains and the Upper Midwest should expect temperatures to hover over the historical average for the weekend and into the first half of next week.

For instance, places such as Billings, Montana, will see temperatures hover around the 80-degree mark over the weekend. Plentiful sunshine will make it feel even warmer. Overnight lows will slide into the upper 40s, creating dramatic temperature changes within a few hours. This pattern will come to an abrupt halt on Monday with a forecast high of just 47 degrees. The chance of light snow is on the horizon for Tuesday morning in the college town.

Rapid City, South Dakota, is in store for a lovely weekend, particularly by early May standards. This part of the northern Plains will see a high of 76 degrees on Saturday, followed by readings that reach the 80-degree barrier on Sunday. Unfortunately, Sunday's sunny and warm weather will also come with gusty conditions. Winds will be whipping around from the south-southeast at 15 to 25 mph. Overnight lows will bounce around in the upper 40s to low 50s over the weekend in Rapid City.

It will take a bit longer for the unseasonable warmth to arrive in the Upper Midwest. Minneapolis is forecast to see a high of 76 degrees on Sunday, a change of about 10 degrees from Saturday's highs. Tuesday will likely be the first day in this stretch in which the mercury breaks the 80-degree mark.

Cooler Temperatures, the Story for the Southern Tier of the U.S.

It will be a different situation to the south of the blocking pattern. The swath of land from the Desert Southwest and over to the South will see the mercury dip to levels lower than that is typical for early May.

For example, Las Vegas will top out with a high of just 69 degrees on Sunday. Sin City will see cloudy skies to bring the weekend to a close, ushering in the chance of a stray rain shower during the afternoon hours. The chance of rain will increase after the sun goes down on Sunday with readings that slide into the upper 50s. It will be gloomier on Monday on The Strip with highs that only hit the mid 60s and scattered rain showers. The mercury will begin to climb again on Monday, reaching the low 90s again by the end of the work week.

Florida and portions of South Texas will likely be the other areas of the southern U.S. that will see consistent temperatures in the 70s and 80s through the first part of next week.

Did you find this content useful? Feel free to bookmark or to post to your timeline for reference later.