Update, Saturday afternoon, 2:20 p.m., from the National Weather Service, Little Rock:

Several waves of showers and thunderstorms will affect Arkansas through the weekend. Heavy rainfall is likely, and severe thunderstorms are a possibility.

.Heavy Rainfall...
As waves of showers and thunderstorms move across the state today through Sunday, rainfall will be heavy at times.

Heavy rain will be most likely over northern Arkansas, primarily in the Ozark and Ouachita Mountains. Rainfall amounts in excess of six inches are likely, mainly in areas north of a line from Fort Smith to Pocahontas. Localized amounts of eight inches are possible.

The heaviest rainfall is expected today and tonight. Already in the last few days, heavy rain has fallen over northern and northwest Arkansas. Additional rainfall on nearly saturated ground will yield the threat of flash flooding.

Stages are high on some area rivers, with some locations on the White River and its tributaries already in minor flood. Heavy rainfall will not only prolong the high stages, but is expected to cause minor to moderate flooding in most basins, and major flooding along the White River basin. These rises are expected to be long-term, likely keeping some areas along the White River above flood stage well into May.

.Severe Thunderstorms...
Severe thunderstorms are possible through tonight, and into Sunday morning in much of Arkansas.

This morning, a warm front was located across the northwest corner of Arkansas and not moving much. Showers and thunderstorms are mainly north of the front. South of the front, the atmosphere is more capped, which is inhibiting thunderstorm development.

All modes of severe weather are possible. North of the frontal boundary, the greatest severe weather concern will be large hail and damaging winds. Near and a little south of the boundary, the tornado potential will be highest.

A cold front will approach Arkansas from the west later today. Showers and thunderstorms will develop out ahead of the front, primarily during the afternoon and through the overnight hours. All portions of the state will carry about the same risk of severe thunderstorms…an Enhanced Risk.

Today through tonight, large hail and damaging winds are the primary concerns. With the amount of wind shear over the state, tornadoes will also be a concern, especially during the afternoon and early evening hours.

On Sunday, the cold front will move into central Arkansas in the morning and exit eastern Arkansas during the afternoon. There will be a risk of severe thunderstorms on Sunday, primarily in areas near and a little west of the Mississippi River…Marginal Risk.

Rainfall will gradually come to an end by Sunday evening.

-end update-

As always, please continue to monitor the latest information from your Arkansas National Weather Service Forecast Offices, and be prepared to take action if a watch or warning is issued for your area.

People in low-lying and poor drainage areas need to monitor the latest weather conditions. This is especially true for those near the banks of rivers and streams. Take all warnings seriously, and be prepared to move to higher ground if necessary.

Update, Friday morning, April 28, 10:30 a.m., from the National Weather Service, Little Rock:

A very unsettled weather pattern is expected today through Sunday. Severe weather and excessive rain appear likely at this time.

Today, a warm front is expected to move north across Arkansas. North of the front, showers and thunderstorms will develop mainly north of Little Rock.

Any storms that develop along or south of the warm front this afternoon through tonight will have a chance of becoming severe. Only isolated storms are expected along or south of the front, but if storms develop here, they will be capable of producing large hail, damaging winds and tornadoes.

Precipitation across the northern counties will be ongoing heading into Saturday. Later in the day, a storm system in the Plains will drag a cold front toward the state. Ahead of the front, a large area of showers and thunderstorms will sweep through the region Saturday night and Sunday.

Tornadoes, damaging winds, and large hail will once again be possible with this long duration event. More than a half foot of rain could fall in the northwest half of Arkansas.

If this pans out, widespread and life threatening flash flooding would occur. Also, area tributaries would flood, including the Black, Buffalo, Cache, Eleven Point, Fourche La Fave, Petit Jean, Spring, and White Rivers.

Forecast details are still being worked out, including where the warm front will set up today, and the timing of the aforementioned bouts of precipitation. Please continue to monitor the latest forecasts from your National Weather Service concerning this potentially dangerous situation.

-end update-

From the National Weather Service, Little Rock: 

A very unsettled pattern is expected Friday through Sunday. Severe weather and excessive rain appear likely at this time.

On Friday, a warm front is expected to move north across Arkansas. North of the front, showers and thunderstorms will develop mainly north of Little Rock, especially during the overnight hours.

Any storms that develop along or south of the warm front Friday afternoon through Friday night will have a chance of becoming severe. Only isolated storms are expected along or south of the front, but if storms develop here, they will be capable of producing large hail, damaging winds and tornadoes.

Precipitation across the northern counties will be ongoing heading into Saturday. Later in the day, a storm system in the Plains will drag a cold front toward the state. Ahead of the front, a large area of showers and thunderstorms will sweep through the region Saturday night and Sunday.

Tornadoes, damaging winds, and large hail will be once again be possible with this long duration event. More than a half foot of rain could fall in the northwest half of Arkansas.

If this pans out, widespread and life threatening flash flooding would occur. Also, area tributaries would flood, including the Black, Buffalo, Cache, Eleven Point, Fourche La Fave, Petit Jean, Spring, and White Rivers.

Forecast details are still being worked out, including where the warm front will set up on Friday, and the timing of the aforementioned bouts of precipitation. Please continue to monitor the latest forecasts from your National Weather Service concerning this potentially serious situation.