Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/05/18


Area Forecast Discussion
National Weather Service Hastings NE
543 PM CST Thu Jan 4 2018 .SHORT TERM...(This evening through Friday) Issued at 323 PM CST Thu Jan 4 2018 Skies are mostly clear across the forecast area this afternoon. With westerly winds, the temperatures have warmed up to near or above freezing. The main concern for tonight into Friday morning will be fog. With some snow melt going on and the current dew points warmer than the current forecast lows, there could be some fog around. On the flip side, there will be some wind tonight, even if it is light, and it should be from the north. Have decided to keep mention of some patchy fog mainly in the west, but wonder if there may be some further to the east as temperatures in the east rise to around freezing as well. The fog will last for a while in the morning before dissipating. There will be a cold front that pushes into the area from the northeast during the night. That will keep the temperatures on the colder temperatures tonight. The colder temperatures will push into the forecast area during the day on Friday. There will be an increase in clouds as the colder air moves into the area. .LONG TERM...(Friday night through Thursday) Issued at 323 PM CST Thu Jan 4 2018 There are a few periods of interest during the period. First, will be the warming trend for the weekend. After the cold on Friday, there will be warm advection for Saturday and with some clearing, the temperatures will warm a little. Temperatures continue to warm on Sunday, but at the same time there is an upper level wave that moves through the area and gives a chance for precipitation. The models have had some differences from run to run and model to model so there is some uncertainty, but there appears to be at least a small chance for mainly the southeast part of the forecast area. The problem with this is there will be some mixed precipitation. Have decided to keep some sleet in the forecast, but with the trend toward less precipitation will have to see how much there will be. The warming trend continues Monday and Tuesday as well and temperatures remain steady for Wednesday. Tuesday appears to be the warmest day of the week. The next period of interest will be Wednesday afternoon into Thursday. There is an upper level low moving through the plains during this time. A surface low and cold front move through, as well. There have been a few differences in the models. The 12Z GFS and the 00Z ECMWF were similar, but the 12Z run of the ECMWF is a little slower. The Canadian is slower and weaker than either of them. As it looks at this time, there could be some rain as early as Wednesday afternoon for much of the forecast area, but the cold air moves into the area later in the afternoon and continues to push through during the evening. Most of the area will just have rain changing to snow, but the far southeast could see a little sleet during the transition to snow. With some of the model differences, will have to keep an eye on this system as it approaches the area. && .AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Friday) Issued at 528 PM CST Thu Jan 4 2018 Stratus currently across the Dakotas will sink into the area after midnight tonight. The expectation is still that ceilings may drop to IFR, but I have delayed the onset of the lowest ceilings to near dawn tomorrow. This better matches the RAP model guidance. Winds will remain light and variable tonight, which when coupled with moisture from the melted snow, may lead to some patchy fog as well. Models remain variable on location, but the western edge of the stratus deck is probably the most favorable, therefore I believe Kearney stands a better chance to see reduced visibility. IFR ceilings are expected to lift to MVFR by mid morning, but stratus will likely hang around for most, if not all, of the daylight hours on Friday. && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ SHORT TERM...JCB LONG TERM...JCB AVIATION...Mangels
Area Forecast Discussion
National Weather Service Grand Rapids MI
1025 PM EST Thu Jan 4 2018 LATEST UPDATE... Update .SYNOPSIS... Issued at 330 PM EST Thu Jan 4 2018 We will remain bitter cold into the weekend. Wind chill readings will become dangerously low tonight, ranging from 10 below zero near the lake to 25 below zero well inland. Lake effect snows will continue, especially west of U.S. 131, where another 3 to as much as 9 additional inches can be expected through Saturday. All areas should see snow Sunday and Sunday night and again Thursday of next week. Temperatures will finally warm next week, when most daily highs should be in the 30s. && .UPDATE... Issued at 1023 PM EST Thu Jan 4 2018 The good radiational cooling inland has supported lower temperatures. Some mesonet stations were already around -10 degrees in NW Kent County. UPDATE Issued at 850 PM EST Thu Jan 4 2018 Skies have scattered out away from the lakeshore. This forecast update reflects less in the way of cloud cover for these locations for the rest of tonight. Temperatures were also lowered as less cloud cover is expected. The main band of snow remains west of Muskegon. The Latest ESRL HRRR does bring some banding onshore later tonight around Muskegon. Not sure if this will be the case given the colder temperatures over the inland areas. For now will keep the headline going. Where the band is onshore...impacts were occurring. && .SHORT TERM...(This evening through Saturday) Issued at 330 PM EST Thu Jan 4 2018 Little change expected through Saturday. Arctic air will remain in place. Highs Friday and Saturday will be in the single digits inland to around 15 toward Lake Michigan. Overnight lows will drop toward minus 10 each night, but a bit warmer toward the lake where clouds prevail. Winds will be fairly light, but still adding to the chill. Will have a wind chill advisory for all areas except the lakeshore counties. Wind chill readings of -15 to -25 will be commonplace tonight. The far northern interior could even flirt with wind chill warning criteria. As far as the lake effect, it will continue into Saturday, before finally diminishing Saturday afternoon. Mean low level wind remains 335-350 through the next 48 hours and the moisture remains deep enough to expect little overall change. The headlines along the coastal counties will continue. Generally expect 3 to 9 inches over the next 48 hours in the headline region. .LONG TERM...(Saturday night through Thursday) Issued at 330 PM EST Thu Jan 4 2018 The main highlight of the long term period is that warmer temperatures are finally expected. We begin the temperature rebound on Sunday with southerly winds on the back side of a departing sfc high, with high temperatures reaching 25 to 30 degrees. On Monday it looks like most of the area will reach or exceed freezing, then only a minor cool down occurs on Tuesday before another warm up ensues for Wednesday into Thursday when highs near 40 are not even out of the question. The polar jet retreats during this time and a srn stream trough over the central plains helps develop a downstream ridge over the Great Lakes Rgn. It should be noted that there is still decent ensemble spread for the mid to late part of next week in terms of how warm it may get, but is certainly something to watch. In terms of precipitation events, it still looks like some light snow can be expected in the warm advection pattern on Sunday into early Monday, then perhaps some scattered snow (or rain?) showers toward the mid to late part of next week as developing srn stream system starts sending some moisture our way. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 623 PM EST Thu Jan 4 2018 Generally looking at VFR weather at the TAF sites tonight. Band of snow just west of KMKG is forecasted to move slowly east and break up somewhat. Based on that...I do feature some snow for that TAF site later this evening. Clouds may redevelop during the afternoon inland. Thus I featured afternoon MVFR for KLAN and KJXN. && .MARINE... Issued at 330 PM EST Thu Jan 4 2018 Brisk NNW winds continue around 25 knots and the small craft advisory will be maintained. && .HYDROLOGY... Issued at 330 PM EST Thu Jan 4 2018 The advisory continues at Evart. However, we have coordinated with the Evart Police Department and Public Works about river conditions. For now, there is no immediate threat with no impacts being observed/reported. Despite some erratic behavior on a few other gauges, readings are purely ice affected. Overall, levels are below action stage and seem to be fairly stable. The question lies in next week`s temperature transition. Yesterday it seemed that we would approach or slightly top freezing. Members in some of the latest guidance are well into the 40s. The cooler solutions are in the upper teens. Generally speaking, when solid river ice forms, free movement can occur with a couple of days (or more) near 50 degrees. There is some confidence in milder weather, but the extent of the warmth is still uncertain. If temperatures trend warmer in guidance, we may need to keep an eye on river levels next week. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...Winter Storm Warning until 7 AM EST Saturday for MIZ064-071. Wind Chill Advisory until 11 AM EST Friday for MIZ038>040- 044>046-051-052-057>059-065>067-072>074. Winter Weather Advisory until 7 AM EST Saturday for MIZ037-043- 050-056. LM...Small Craft Advisory until 10 AM EST Saturday for LMZ844>849. && $$ UPDATE...MJS SYNOPSIS...JK SHORT TERM...JK LONG TERM...Meade AVIATION...MJS HYDROLOGY...JAM MARINE...JK
Area Forecast Discussion
National Weather Service Blacksburg VA
921 PM EST Thu Jan 4 2018 .SYNOPSIS... Strong Arctic high pressure will gradually build in from the northwest tonight through Saturday resulting in continued bitterly cold temperatures and low wind chills. The center of the high should pass overhead by the end of the weekend ahead of the next complex area of low pressure that arrives for early next week. && .NEAR TERM /THROUGH FRIDAY/... As of 915 PM EST Thursday... No changes were made in time or location to the current wind chill advisories/warnings. Over the past 1-2 hours, an uptick in wind gusts has been observed as another vort lobe swings through our area as seen on GOES-east. The HRRR low level wind forecast has a good handle on this trend and indicates low level winds peak around 06Z, and it is not until after 10-12Z before wind begin to diminish. Pushed up wind gusts a few MPH in the forecast update and lowered temps a degree or so. Bands of light snow continue to bleed into the foothills of VA, and expanded low POPs east to cover these areas including Carroll, Floyd and Franklin counties. High-res model soundings show depth of shallow moisture layer not diminishing until Friday morning. While this will fall for several hours, the very high snow-liquid ratio will keep accumulations light. Expect both snow showers and winds to decrease some Friday morning as the low level flow briefly turns more westerly and forecast soundings show the depth of moisture decreasing from above as the inversion lowers. However still enough to keep some flurries/snow showers going just from the cold advection so keeping in clouds/pops west and mainly clear east. Better subsidence along with even drier air will work in during Friday with lingering snow showers likely early across the west before shrinking in coverage from south to north by afternoon. Winds should still be gusty but not quite as strong as today with the pressure gradient slowly weakening as low pressure pulls farther away. However still cold enough for advisory level wind chills to linger until midday and perhaps all day across the mountains espcly where clouds linger. Otherwise despite more insolation, little change in 85h temps suggests highs mostly teens west to around 20 Blue Ridge, and mid/upper 20s east where slight downslope warming should help a bit given the dry air. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/... As of 215 PM EST Thursday... Very cold with gusty winds and dangerous wind chills into the weekend, some moderation Sunday. Arctic high pressure will continue building down from the upper midwest and will bring the core of the cold air through the region Friday night and Saturday. Winds will also remain blustery and create very low wind chill values through Saturday morning. Lingering upslope snow showers/flurries will also continue west of the Blue Ridge with some light additional accumulation possible mainly at the higher elevations around western Greenbrier county WV. As the center of the high drifts over the region Saturday night conditions, winds will slacken and there should be a window of time with good conditions for radiational cooling before mid/high clouds move in and winds shift to the southeast late. If clouds are slower to move in and a strong enough surface inversion can become established to keep winds at bay, temperatures could really plummet to some impressively cold lows by daybreak Sunday. As the high moves off to our east on Sunday and winds become southerly we will finally start to break out of the cold. The persistent upper low that has been keeping the cold air locked in over the eastern US will give way to a much more progressive and warmer pattern. A very brisk southwesterly low level jet will start advecting warmer air in the region, and good isentropic lift will develop Sunday night ahead of a frontal system approaching from the west as the region gets split by low pressure moving by well to our north and south. Low level moisture return will be slow so it looks like the better chances for precipitation will be holding off until mainly after daybreak Monday. && .LONG TERM /MONDAY THROUGH THURSDAY/... As of 215 PM EST Thursday... Definitely trending to a warmer synoptic pattern next week as progressive low amplitude flow evolves to a deepening trof in the west with sympathetic ridging in the east. Expect temperatures to be at or slightly above normal by midweek. Cold front will be moving through the region Monday/Monday night with a good chance of precipitation. With all of the warming aloft and cold air at the surface Bufkit soundings have a distinct look of freezing rain, especially given the very cold ground temperatures coming off our spell of cold weather. The combination of QPF and cold temperatures looks favorable for a decent glaze of black ice Monday before surfaces go above freezing. Will continue to assess potential impacts with later model runs. As this system pulls away on Tuesday we can expect some lingering upslope rain/snow showers west of the Blue Ridge, followed by generally dry weather through midweek. && .AVIATION /02Z FRIDAY THROUGH TUESDAY/... As of 635 PM EST Thursday... A strong storm system off the New England coast this evening will continue to move away from our area, but strong northwest winds in the wake of the system will keep persistent MVFR cigs to mountain TAF sites including KBCB, KBLF, and KLWB through at least Friday morning. Ceiling may drop to IFR levels at KLWB and KBLF tonight with localized snow showers. East of the Blue Ridge (KROA/KLYH/KDAN), VFR conditions should continue with ceilings at ROA remaining at VFR levels. Very strong northwest winds will continue to create issues with flying through Friday morning with gusts to 40+ knots possible over the mountains, and 30+ knots possible across the Piedmont locations. Of note...the observation from KDAN is unavailable due to problems with power from early this morning. Will continue to provide a forecast TAF without a NIL AMD since VFR and winds remain the only issue at this point. Extended Discussion... A prolonged period of strong northwesterly winds with MVFR to flight restrictions due to upsloping clouds and snow showers will persist west of the Blue Ridge into Friday night/early Saturday East of the Blue Ridge, gusty downsloping winds will maintain VFR flight conditions across the Piedmont. Arrival of the surface high pressure system on/by Sunday will bring diminishing winds, a return to widespread VFR weather (even in the mountains), and slowly moderating temperatures. Arrival of a fast moving low pressure system may result in another round of sub-VFR flight restrictions mainly west of the Blue Ridge on Sunday night - spreading east across the Piedmont on Monday. Widespread MVFR to IFR restrictions with a wintry mix of precipitation gradually transitioning over to rain is expected as the system moves northeast through the region on Monday. Return to VFR across the region should occur on Tuesday with perhaps only some lingering MVFR cigs across the mountains early on. && .FIRE WEATHER... Antecedent conditions are dry. In spite of the cold, the dryness of the current Arctic airmass and lack of meaningful precipitation the last 30-60 days is beginning to set the stage for potential fire concerns. Sun angle is low so the active burn window is small, however with little or no moisture recovery at night conditions are becoming favorable to sustain fire starts if they occur. Ignition sources for this time of year given the cold weather would most likely come from hot ashes being dumped out by folks using wood stoves. && .CLIMATE... A continued series of Arctic air masses is expected during the next 3 or 4 days, likely threatening record low maximum temperatures and perhaps even record low minimum temperatures. Here are the records for the next several days. Climate Records Summary Thursday 01/04/2018 Site LoMax Year KBLF 17 2010 KDAN 26 1979 KLYH 22 1919 KROA 24 1919 KRNK 19 1979 Friday 01/05/2018 Site MinT Year LoMax Year KBLF -4 1981 14 1999 KDAN 9 1958 25 1981 KLYH 1 1969 21 1959 KROA 5 1969 16 1912 KRNK -2 1981 12 1981 Saturday 01/06/2018 Site MinT Year LoMax Year KBLF -4 2014 14 1988 KDAN 10 1999 27 1999 KLYH 3 1924 18 1912 KROA 2 1924 18 1912 KRNK -2 2014 13 1959 && .EQUIPMENT... As of 400 AM EST Thursday... Several stream and river gages have been reporting bad data, and is due to ice affecting the gage. Most of these have been deactivated on our web page. Given the dry conditions, the threat of flooding is zero. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...Wind Chill Advisory until noon EST Friday for VAZ007-009>019- 022>024-035. Wind Chill Warning until noon EST Friday for VAZ020. Wind Chill Watch from Friday afternoon through Saturday morning for VAZ020. Wind Chill Advisory until 10 AM EST Friday for VAZ032>034- 043>047-058-059. NC...Wind Chill Advisory until noon EST Friday for NCZ001-002-018. Wind Chill Advisory until 10 AM EST Friday for NCZ003>006-019- 020. WV...Wind Chill Advisory until noon EST Friday for WVZ042>044-507. Wind Chill Warning until noon EST Friday for WVZ508. Wind Chill Watch from Friday afternoon through Saturday morning for WVZ508. && $$ SYNOPSIS...JH/WP NEAR TERM...JH/PH SHORT TERM...MBS LONG TERM...MBS AVIATION...JH/PH FIRE WEATHER...PM CLIMATE...RAB/WP EQUIPMENT...WP