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There may be some changes in May for those in the South and along the East Coast, where a break from cooler-than-average temperatures is likely, at least for the beginning of the month, according to the latest outlook from The Weather Company, an IBM Business.

A familiar temperature pattern is expected in May with the West experiencing above-average temperatures, while the Midwest and Great Lakes continue the trend of below-average conditions.

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Above-average temperatures are anticipated to persist from April into May across the West, with temperatures well-above-average from California into the Southwest and Great Basin. This is in response to an upper-level ridge of high pressure or northward bulge in the jet stream that is expected to dominate the region for much of May.

Those in the northern Plains, Ohio Vally, Midwest and Great Lakes regions that were hoping for a pattern change in May will likely be disappointed as colder-than-average conditions are once again expected here.

The first week of May will bring anomalously warm temperatures to the Northeast, which has tipped the forecast to near to slightly-above-average conditions in May for the East.

The above-average temperatures that will begin the month in the East, however, may be tough to sustain notes Dr. Todd Crawford, chief meteorologist with The Weather Company. There are several signals that the recent colder trend in the eastern U.S. over the last few months will return after the first week of May.

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One factor that may influence temperatures across the U.S. in May is the greater-than-average snow cover in April.

Although snow cover will be less impactful on temperatures in May than April, it "appears to have an impact on the pattern, either via local albedo impacts, enhanced soil moisture after snow melt, or via direct impact on the synoptic pattern from reduced sensible heat flux into the atmosphere," says Crawford. What this means is that less heat, an increase in reflectivity and more moisture at the surface has an impact in the atmosphere and the resulting weather pattern.

Crawford also notes that in addition to the unusual April snow cover and other signals in the atmosphere, the lack of anomalous warmth to start the month across the northern Plains and Great Lakes supports the expectation for below-average temperatures there.

(MAPS: 10-Day Forecast)

Average Temperatures in May

It's important to keep in mind the forecast is an overall expectation for the month, and the forecast is compared to average temperatures.

Above- to much-above-average temperatures from California into the Great Basin and Southwest would indicate more summerlike conditions here.

Slightly-above-average temperatures across the South in May would translate into highs generally in the 80s and 90s.

However, cooler-than-average temperatures from the northern Plains into the Midwest could mean chilly conditions with highs more typical of what is expected in early spring.

(MAPS: Average High and Low Temperatures)

Below-average temperatures in the northern Plains and Midwest also suggest fairly cold low temperatures, given that average lows for May range from the 30s to 50s here.

In the West, above-average morning lows would mean mild temperatures for many areas, with warm overnight conditions in the Southwest.