A Fall pattern continued into mid-October, 2007...with storm systems/fronts arriving every few days from the west. One such front pushed into Arkansas on the 15th, and brought widespread rain.
In the picture: The weather pattern on 10/15/2007 featured a cold front pushing into Arkansas from the Plains...with a lot of rain ahead of the front.

The rain kept afternoon temperatures in the 60s across much of the region, and prevented the atmosphere from becoming too unstable (which decreased the chances for severe storms).
In the picture: Clouds and rain kept temperatures down during the afternoon of 10/15/2007.

	Much of central and southern Arkansas received 1 to 2 inches of rain (with locally heavier amounts). Twenty four hour amounts through 1 am CDT on the 16th included 1.98 inches at Mount Ida (Montgomery County) and Texarkana (Miller County), with 1.85 inches at Hot Springs (Garland County) and 1.79 inches at Russellville (Pope County).
In the picture: Twenty four hour rainfall amounts through 1 am CDT on 10/16/2007. Scattered 2 inch amounts (or more) occurred in the counties in red (mainly in southern Arkansas).

The front stalled along the Gulf Coast, with moisture bottled up. A new storm system in the Pacific Northwest spun up strong low pressure in the central Plains on the 17th.

The low pulled Gulf moisture into Arkansas, and it warmed up (afternoon temperatures in the 70s to lower 80s). The atmosphere became very unstable, with severe weather likely.
In the picture: The pattern on 10/17/2007...with a storm system in the Pacific Northwest inducing strong low pressure ("L") in the Plains, and bringing severe weather to Arkansas.

	There was a lot of wind energy present ahead of the system, with storms forecast to move quickly. This increased the potential for wind damage. In addition, there was a southeast wind near the ground and a west to southwest wind aloft...which created a turning motion with height. Given this, tornadoes were possible.
In the picture: Helicity/shear (representing the potential for rotating winds) was high (over 200 m2/s2) and CAPE (Convective Available Potential Energy...or a measure of instability) was increasing (to over 1000 J/kg) across much of Arkansas on 10/17/2007. The graphic was constructed using data from the Storm Prediction Center in Norman, OK.

More Information

There is more concerning the storms of October 15th-18th. To check out the rest of the story, click here.