Area forecast discussion National Weather Service La Crosse WI 1209 PM CDT Sat may 25 2013 Short term...(today and tonight) issued at 230 am CDT Sat may 25 2013 Low/middle level frontogenetic forcing...coupled with some low level moisture transport and a bit of upper level energy...were helping continue an area of east/southeast moving showers. Trends in the latest hrrr/nam12 is to diminish this activity through the pre dawn hours...while firing convection over the Southern Plains/western Iowa. Satellite imagery and radar returns already show this happening...where the nose of the low level jet/moisture transport was located. This complex should move east through the rest of the morning into the afternoon...riding along and north of a warm front. This region should serve as the focus for more shower/storm development tonight...with the low level jet reasserting itself and some upper level energy moving out of a West Coast trough. Eastward movement would again be favored...keeping the bulk of the precipitation south of the forecast area. Long term...(sunday through saturday) issued at 230 am CDT Sat may 25 2013 High confidence its going to rain across parts of the region through the upcoming work week. Timing and placement is more shaky. The forecast Keys on a few areas...a surface warm front...low level jet/moisture transport...and various mcvs. Where these elements all come together will be where the greater threat for rain will lie. Clarity for the mesoscale vorticies/spawning grounds and movement is the main sticking point for increasing confidence. The upper level pattern is slow to progress east as there is little impetus via 250/300mb jet interaction - relatively quiet a loft. So...the 500 mb ridge will remain across the upper Mississippi River valley/Great Lakes into at least the middle part of the new work week...with a broad trough over the West Coast. Bits of energy will spin out of the trough...and then enhance via convection spawned by it and the low level jet/moisture transport. With the ridge overhead the next few days...and the surface warm front holding to the south...these upper air inflections are prognosticated to ride along and north of the warm front...keeping the best rain chances just south -but not completely out- of the forecast area. The warm front will start to lift north on Tuesday...a fairly consistent signal in the NAM/GFS/ECMWF. How far north is not though...with the GFS appearing the more aggressive in how far north and how fast. Rain chances look to become more widespread for the forecast area Monday-Tuesday as a result. Depending on how quickly and how far north the warm front makes it...the area could get into the warm sector...which would help cap off the atmosphere to convection - outside of a kicker moving in. Model differences start to become bigger as we move toward next weekend...with the ec suggesting a closed low will develop in the West Coast trough...slowly pushing east across the upper Mississippi River valley next weekend. This could lay up a surface trough across the region for several days. The GFS is more progressive...moving the upper level energy northeast...but still has a couple surface boundaries that could act as shower/storm producers. Will likely stay with the consensus solution for the details in this part of the forecast. As for storm chances...instability is limited the next couple days...and so should be the thunderstorms. The chance for boomers will increase with the encroachment of the warm front...and subsequent increase in convective available potential energy. Don/T see a significant threat for organized severe weather through next week. && Aviation...(for the 18z tafs through 18z Sunday afternoon) issued at 1208 PM CDT Sat may 25 2013 Area of MVFR ceilings over southern into western Minnesota has slipped into krst. The 25.15z rap indicates these should remain through about the middle of the afternoon before they rise to a low VFR level from the heating of the day. The concern for the overnight hours is whether the next convective complex will impact the taf sites. The 25.12z NAM along with the 25.06z hi-res arw both suggest the warm front will remain south of the area. The next complex is expected to develop over South Dakota and then ride southeast along the front moving across Iowa into Illinois staying south of both airports. At this point...will not even include a vcsh but will lower the ceilings expecting the northern edge of the lower clouds from the convective complex to impact both airports. The NAM BUFKIT soundings shows krst going down to MVFR with klse staying VFR. && Arx watches/warnings/advisories... WI...none. Minnesota...none. Iowa...none. && $$ Short term...rieck long term....rieck aviation...04