611 FXUS65 KBOU 101708 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1108 AM MDT Sun Mar 10 2019 .UPDATE... Issued at 1036 AM MDT Sun Mar 10 2019 Just minor adjustments planned for the grids at this time. Denver cyclone over Denver with gusty southerly winds over southern and eastern parts of Denver. Adjusted the temperatures up a couple of degrees in those areas for this afternoon. Those winds around Denver should decrease and become more variable later this afternoon. Lessened the cloud cover over the northeast plains as well. In the mountains, just some light snow showers possible north of I-70. This already addressed in the forecast so no adjustments there. && .SHORT TERM...(Today and tonight) Issued at 454 AM MDT Sun Mar 10 2019 SW flow aloft will be over the area thru tonight. Cross-sections continue to show moisture embedded in the flow which will bring additional light snow to the nrn mtns, especially, zns 31 and 33. Across nern CO it will be dry. As far as highs, am getting conflicting signals on readings across nern CO. Hi res data is yielding highs in the upper 40s to mid 50s while other guidance suggests highs mainly in the mid to upper 40s. Have used a blended approach and kept high in the mid 40s to around 50. For tonight moisture will decrease in the mtns, thus light snow should gradually end in the evening hours in the mtns. Across nern Co it will remain dry. A cool front will affect the plains overnight. The NAM is very aggressive in bringing areas of fog across portions of nern CO after 09z while the other models not so much. .LONG TERM...(Monday through Saturday) Issued at 454 AM MDT Sun Mar 10 2019 Models show strong southwesterly flow aloft over our forecast area Monday into Tuesday afternoon. By Tuesday evening/night, there is a decent upper trough from the northwestern U.S. Rockies south-southeastward down into southwestern New Mexico. There are a couple main pieces of energy with it. By 12Z Wednesday morning, there is an upper closed low circulation over northeastern New Mexico, with energy still to our west and northwest. There is weak upward vertical velocity on the QG Omega fields mid day Monday into Tuesday afternoon. The upward energy gets stronger Tuesday night. The low level pressure and wind fields show a Denver cyclone around on Monday, with southeasterly winds over most of the plains all day. Drainage winds look like a good bet on Monday night. There could be another cyclone on Tuesday, with most areas looking at southerly winds. A cold front gets into the CWA between 06Z-12Z Tuesday night/Wednesday morning associated with the upper trough. There is significant upslope flow behind the front. Looking at moisture, there is decent moisture in the mid and upper level early on Monday, with an slight increase through the day, especially over the mountains. The NAM has a shallow layer of low level of moisture over some of the plains early, but none of the other models show this. By Monday night, there is a bit of low level moisture over the eastern plains in the evening, with a bit of a decrease in the moisture elsewhere. Moisture increase later on Tuesday, and especially Tuesday night with the incoming trough. Overall, the southwesterly flow aloft is bringing quite a bit of moisture and the precipitable water value are quite high for this time of year. For pops, will leave them pretty high for Monday afternoon and Monday night in the mountains and eastern plains. Will also leave in the chance of Freezing precipitation over the far east as per forecast soundings. For temperatures, Monday's highs are a bit cooler than today's with a 3-8 C warm up for Tuesday's highs. For the later days, Wednesday through Saturday, many of the ECMWF and GFS parameters agree fairly well with the storm continuing through Wednesday, even into early Thursday. The QPF amounts are fairly high on both models. A decent precipitation event continues to look good, with strong enough low level winds, at least, over the eastern plains for blizzard conditions on Wednesday. Will keep the high pops in for this package. By Thursday night, the upper trough is through the CWA with northwesterly flow aloft behind it. Zonal flow in progged on Friday with another weak upper trough Friday night into Saturday. Upper ridging moves in after that. && .AVIATION...(For the 18Z TAFS through 18Z Monday afternoon) Issued at 1036 AM MDT Sun Mar 10 2019 A Denver Cyclone will continue to produce a tricky wind forecast this afternoon. At this time, still expect gusty southerly winds this morning will decrease and transition to north/northwesterly this afternoon at DIA. Current data suggests the low will move north of DIA by early aftn with winds shifting north and east of DIA allowing for a more northerly direction. Late tonight a cool front will move across. May see areas of low clouds develop after 09z. NAM is also showing dense fog developing while the HRRR isn't. Blended solution from DAS is indicating IFR ceilings but no fog. Will keep the mention some lower ceilings but no fog in 12z taf. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Cooper SHORT TERM...RPK LONG TERM....RJK AVIATION...Cooper