Eastern NE/Western IA Hazardous Weather Outlook 5-4-12

Weather

May 4th, 2012 by Ric Hanson

FOR MONONA-HARRISON-SHELBY-POTTAWATTAMIE-MILLS-MONTGOMERY-FREMONT & PAGE COUNTIES IN WESTERN IOWA….

THERE IS A SLIGHT RISE FOR SEVERE STORMS ACROSS ALL OF THE OUTLOOK AREA BEGINNING LATE THIS AFTERNOON IN NORTHEAST NEBRASKA…THEN THROUGH THE EVENING ACROSS THE REST OF EASTERN NEBRASKA AND SOUTHWEST IOWA. LARGE HAIL WILL BE THE PRIMARY HAZARD WITH DAMAGING DOWNBURST WINDS A SECONDARY CONCERN.

INCREASING HUMIDITY ON SOUTH WINDS ALONG WITH AFTERNOON HEATING WILL PRODUCE A VERY UNSTABLE ATMOSPHERE IN THE OUTLOOK AREA. A STATIONARY FRONT DRAPED ALONG THE SOUTH DAKOTA BORDER SHOULD PROVIDE THE FOCUS FOR THUNDERSTORM DEVELOPMENT THIS AFTERNOON…AIDED BY A MID LEVEL WAVE MOVING IN FROM THE WEST. ANY STORM THAT DEVELOP NEAR THIS STATIONARY WILL HAVE A SMALL CHANCE TO PRODUCE A TORNADO. THIS ACTIVITY IS EXPECTED TO DRIFT OR DEVELOP SOUTHEAST ACROSS THE REST OF EASTERN NEBRASKA AND SOUTHWEST IOWA DURING THE EVENING…WITH LARGE HAIL POSSIBLE.

SATURDAY THROUGH THURSDAY…

SEVERE THUNDERSTORMS ARE AGAIN POSSIBLE SATURDAY EVENING AND SATURDAY NIGHT. A VERY UNSTABLE ATMOSPHERE WILL BE IN PLACE SATURDAY AFTERNOON BUT WARM MID LEVEL TEMPERATURES SHOULD CAP ANY DEVELOPMENT UNTIL A COLD FRONT APPROACHES FROM THE NORTHWEST. THAT FRONT SHOULD BE MOVING INTO NORTHEAST NEBRASKA DURING THE EVENING…THEN SWEEP THROUGH THE REST OF EASTERN NEBRASKA AND SOUTHWEST IOWA OVERNIGHT. LARGE HAIL WILL BE POSSIBLE WITH ANY
THUNDERSTORMS…EVEN THROUGH THE OVERNIGHT HOURS…AS INSTABILITY WILL REMAIN HIGH.