Who will get rain and who will have sunshine this Mother's Day weekend?

Trouble is brewing for Mother's Day weekend in the form of rain in parts of the South, East and Midwest, while some of the best weather in the nation for outdoor plans, including graduations, will be in the Northwest.

While clearing and dry weather is forecast to advance slowly eastward across the South Central states this weekend, this process will be a slow one. Some areas such as central and eastern Texas may still be dealing with the consequences of torrential rain into Saturday.

While the weather will improve over some areas hit hard with rain, downpours may foil outdoor graduations and holiday gatherings from the lower Mississippi Valley to the Tennessee Valley and southern Appalachians.

Travel to these gatherings could be hazardous in parts of the South.

Locally heavy, gusty and perhaps even a few severe thunderstorms may accompany the rain in this southern swath.

The caboose in the train of storms will be a slow mover and will lunge farther north than many of its predecessors.

Rain is forecast to overspread the Ohio Valley on Saturday and then crawl northward over the central Appalachians, lower Great Lakes and mid-Atlantic during Saturday night.

On Sunday, rain is likely to fall over southern New England and much of New York state. However, there is a chance dry weather from Saturday will hold on across northern New England on Mother's Day.

A separate weak storm will spin slowly southeastward across the northern Plains and the Upper Midwest this weekend. While showers with this feature are likely to be rather spotty, they can be locally robust with a drenching downpour, small hail and thunder and lightning.

This same storm could produce another pocket of wet snow over part of the upper Great Lakes as the weekend draws to a close.

Many areas over the southern Plains can expect a dry weekend with some sunshine.

Perhaps the best weather conditions this weekend in the eastern half of the nation, with the exception of northern New England, will unfold across the Florida Peninsula and the southern Atlantic coast.

In this southern area, an area of high pressure over the Atlantic Ocean will pump warm and humid conditions with most thunderstorms likely to hold off until late Sunday or Sunday night. A stray storm may pop up over South Florida during Saturday afternoon and evening.

In the West, a topsy-turvy weather pattern will continue.

A storm in the upper levels of the atmosphere will generate considerable clouds with showers and locally gusty afternoon thunderstorms from Southern California to portions of Colorado and New Mexico.

People with outdoor plans in this swath should be prepared to take shelter. Those with hiking in mind should use extreme caution over the ridges, due to the risk of lightning strikes and, in the canyons, due to the potential for flash flooding.

A few of the highest elevations over the interior Southwest may receive snow as well this weekend.

Despite the unsettled conditions, there will be breaks of dry weather over the region which may allow some outdoor commencement activities to take place.

Some of the best weather for outdoor conditions across the nation will be in the Northwest.

Sunshine and unusual early season warmth will extend from Washington to Northern California and to much of Idaho, western Montana and northern Utah. Following the severe cold over parts of Montana this winter, the warmth is well-earned.

As a side effect of the warmth, graduation ceremonies in poorly air conditioned venues may become uncomfortable. In some cases, air quality may be poor enough to pose a risk for the elderly and anyone with respiratory problems.

Those who attempt to cool off in area lakes and streams this weekend should use extreme caution as the water temperature is very cold and poses a significant danger.

Even with the forecast of rain in some areas and ongoing flooding in others, all of us at AccuWeather wish you nothing but the best on this Mother's Day weekend.

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