Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 01/20/20

Area Forecast Discussion
National Weather Service State College PA
947 PM EST Sun Jan 19 2020 .SYNOPSIS... An upper level trough will swing through the northeast CONUS early in the upcoming week. High pressure will then settle over the region for the second half of the week bringing perhaps the coldest air of the season. && .NEAR TERM /UNTIL 7 AM MONDAY MORNING/... LE still enducing clouds and -SHSN as of 02Z. There are some large breaks in the cloud deck over Warren and McKean Cos, though. After chatting with BUF and CLE, we agreed that we can probably drop the LES flags as additional accums will be very minor, maybe no more than a dusting. Clearing may come begrudgingly but the HRRR soundings for BFD show the inversion crashing into the ground around sunrise. Kept sky cover a little more pessimistic than total clearing, though. The llvl flow will still be out of the NW all night and into the daylight. Expect mins in the teens and upper single digits. The north may be the spot to bust (too cold of a forecast) if the clouds do not go away appreciably. But, they only have to dip 5-6F to get to the curr fcst mins. Holding the line. && .SHORT TERM /7 AM MONDAY MORNING THROUGH WEDNESDAY/... Aside from some early day snow showers over the northwest mountains and Laurels, Monday will be cold and dry and feature max temps similar to today`s (Sunday), that will range from the upper teens to lower 30s in the SE. These temps are about 6-7F below climate normals for Mid January. Upper ridge and elongated surface high build over the eastern U.S. early in the upcoming week, keeping the rest of the workweek mainly dry with chilly temps 5-10 degrees below normal through midweek. Tuesday and Wednesday mornings will feature some of the coldest air of the season so far. Temperatures should moderate to near normal by Wed afternoon, as the main axis of the high pressure system moves east of our area. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... After a couple of cold days, temps should rise back to normal on Wed and keep climbing a few degrees each day. Even after The potential precip next weekend, temps do not look like they would go back below normal. CPC 6-10 day temperature out look is well above normal, and the 8-14 day is near to above normal for central PA. Prev... An upper level shortwave trough will move into the Pac NW on Tuesday and dig southeastward into the Great Plains region by Friday morning. Some model discrepancies between the ECMWF, with a more amplified solution, and the GFS with more zonal flow. In the 12z Sun ECMWF run, the upper low closes off by Saturday morning and passes south of our area, keeping us in the colder air as some wintry precip spills into the southern half of PA Saturday night. In the 12z Sun GFS run, the upper trough passes over Erie, PA with a broad frontal system moving across the area, with a wintry mix at onset going over to rain as warmer air moves in Saturday, and then back to snow showers behind the cold front Sat night. Ensemble guidance tending towards the GFS so far. Not a surprise given the pattern we have been in, with generally zonal flow and storm tracks going west of us. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... MVFR teetering on IFR conditions for BFD owing to scattered lake effect snow showers through the first part of tonight. MVFR conditions at JST for cigs w occasional drops in vis as isolated snow showers move through. VFR expected this afternoon elsewhere. Gusty westerly winds will continue through early Monday morning. .Outlook... Mon-Tue...Mainly dry, but still a chance of snow showers across the northwest. Wed-Thu...Mainly dry. && .CTP WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until midnight EST tonight for PAZ004. && $$ SYNOPSIS...Dangelo NEAR TERM...Dangelo SHORT TERM...DeVoir LONG TERM...Dangelo/Colbert AVIATION...DeVoir/Banghoff
Area Forecast Discussion
National Weather Service Wilmington NC
1103 PM EST Sun Jan 19 2020 .SYNOPSIS... Arctic air will build into the Carolinas early this week. High pressure will remain to our north through Wednesday, then should move offshore Thursday. An area of low pressure should bring showers late Friday into Saturday, along with milder temps. && .UPDATE... Public: The secondary cold front currently pushing across the FA, should move south of the FA by midnight. In it`s wake, cold and dry air will infiltrate the region, complements of a 1045+ mb Arctic high pressure with it`s center now located across the North Central United States. Have tweaked temps and winds to account for current conditions and trended them toward the overall fcst by midday Mon. Marine: Have tweaked the winds(including gusts) and seas slightly upward to account for current conditions and latest hourly progs ie. HRRR and NWPS. SCA conditions to last likely to midday Mon with plenty of low level mixing over the local waters, a result of the Arctic air moving across mild ocean SSTs, relatively speaking. && .NEAR TERM /THROUGH MONDAY NIGHT/... Initial cold front is now offshore, along with all the light rain. Secondary cold front across our western areas, where dewpoints are dropping quickly, skies are clearing, and winds are become west- northwesterly. Surface high pressure builds in across the central US behind the front, setting up a very cold and dry start to the week. Temps drop to around 30 degrees tonight, and only rise to around 40 degrees Monday under strong cold advection. Add in slightly breezy north winds tomorrow afternoon and dewpoints in the teens, and it will truly feel like winter after a week of spring. Current forecast low for Monday night is around 25 degrees, though model guidance has been trending downward with these values. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... A powerful positively tiled upper trough will pivot across the Southeast states Tuesday, exiting the Georgia and South Carolina coast Tuesday night. 500 mb temperatures below -30C are well below the 10th percentile values for winter and may rank among daily record low values at CHS. Despite the strength of the system aloft, low-level baroclinicity will be focused from the Bahamas to Bermuda, too far south and east to develop a surface system that could lead to precipitation for us. Mainly clear skies and cold conditions are forecast as the low-level cold pool drops into the Carolinas Tuesday, then moves offshore Wednesday. After highs only in the lower 40s Tuesday, forecast lows are in the mid-upper 20s Tuesday night. This is above most MOS guidance as it appears there will be sufficient wind, especially near the coast, to keep the boundary layer well-mixed all night. Temperatures should moderate Wednesday and Wednesday night as warm advection begins and skies remain mostly sunny. && .LONG TERM /THURSDAY THROUGH SUNDAY/... The only system of interest in the extended forecast is expected to move across the Carolinas Friday night, bringing a 12-hour window of rain. Timing with this system has improved considerably among the various models over the past 12-24 hours, and I`ve increased PoPs to 60 percent (likely) for Friday night. High temperatures look like they`ll rebound back into the 60s (above normal) for Friday and Saturday. && .AVIATION /04Z MONDAY THROUGH FRIDAY/... Gusty NW winds have relaxed now that the sun has set and mixing has weakened considerably. Wind dir remains N to NW overnight into tomorrow as high pressure builds in and the sky remains clear. Extended Outlook...VFR conditions thru next week. Arctic high pressure will dominate. && .MARINE... Small Craft Advisory for nearshore waters has been extended through 7am tomorrow morning as seas remain elevated and winds increase again tonight behind secondary cold front. Wilmington Harbor buoy off of Cape Fear currently recording 8ft 6sec S waves. Expect southerly swell heights to slowly decrease through the night into morning. Current westerly winds veer to NW this evening and northerlies by morning, sustained around 20kts overnight with gusts around 25kts. Winds remain northerly Monday and Monday night around 15 kts, with seas 2-4 ft, a 5-6 sec NE wind wave, as the southerly swell dies down by early tomorrow. Arctic high pressure across the Ohio Valley will push cold air out across the waters on Tuesday on northerly winds. Developing low pressure well off the Georgia coast will help to accelerate wind speeds to a solid 25 knots with higher gusts late Tuesday into Wednesday. The potential for even stronger winds out over the Gulf Stream probably means we`ll be dealing with a combination of north wind chop and an east or northeast swell. Small Craft Advisory conditions appear likely. By Thursday low pressure offshore should accelerate out past Bermuda and high pressure will settle across the Mid-Atlantic region. Wind speeds should finally diminish. A warm front ahead of the next low pressure system organizing to our west on Friday should lift a warm front north across the coastal waters, with winds becoming southeast to south by Friday night. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...None. NC...None. MARINE...Small Craft Advisory until noon EST Monday for AMZ250-252-254- 256. && $$ SYNOPSIS...TRA UPDATE...DCH NEAR TERM...VAO SHORT TERM...TRA/SHK LONG TERM...TRA/SHK AVIATION...43 MARINE...DCH/VAO/DCH
Area Forecast Discussion
National Weather Service Lincoln IL
853 PM CST Sun Jan 19 2020 .SYNOPSIS... Issued at 330 PM CST Sun Jan 19 2020 Very cold conditions will persist across central Illinois tonight with temperatures remaining steady in the single digits and teens. A few flurries will be possible as well...particularly during the evening. && .UPDATE... Issued at 853 PM CST Sun Jan 19 2020 As an upper level trough axis continues to slip southeastward, an area of clearing has developed over north portions of central IL this evening, continuing to slip southeastward. At the same time, plenty of light flurries have been noted in the observations around central IL. The 00Z ILX sounding shows a couple of thin cloud layers situated within an ideal dendritic growth zone of temperatures, due to the cold air mass over the area, which is the reason for the prevalence of flurries. Otherwise, winds are still a breezy 10-15 mph mph from the northwest, and temperatures are in the upper single digits in the northwest to upper teens in the southeast. This is well on track with forecasts, and should result in temperatures dropping to the low single digits northwest to low teens southeast, as well as wind chill temperatures ranging from near zero to minus 10. Updates this evening have been mainly for cloud cover trends as well as flurries. && .SHORT TERM...(This evening through Monday) ISSUED AT 330 PM CST Sun Jan 19 2020 A short-wave trough extending from New York to north-central Illinois has resulted in a band of low clouds/flurries across the KILX CWA this afternoon. Partial clearing has occurred in the wake of the wave across southern Wisconsin into northern Illinois: however, this clearing has been making very little progress southward over the past couple of hours. HRRR has been consistently showing the clouds clearing from north to south late this afternoon into early this evening, but based on satellite trends think this is too aggressive. Think partial clearing will occur along/north of a Peoria to Bloomington line this evening, with mostly cloudy conditions holding firm further south across the remainder of the area. May even see a few snow flurries through the evidenced by several 21z/3pm obs along the I-74 corridor. Thanks to the cloud cover and continued northwesterly winds, temperatures will remain nearly steady in the single digits and teens. Next weather-maker is already evident on latest water vapor imagery over southwest Manitoba. This wave is progged to dive southward over the next 24 hours, with the strongest lift skirting central Illinois to the W/SW Monday afternoon. Despite both the 12z and 18z HRRR keeping measurable precip well to the west across northern/central Missouri, other models such as the 12z WRF-ARW and 18z NAM bring very light amounts to the far southwest CWA. With the wave tracking so close and the very cold airmass remaining in place, would not be surprised to see light snow along/southwest of a Effingham line. Any accumulations will be limited to a dusting, with a few tenths of an inch further west along/west of the Mississippi River. High temperatures will range from the teens in the Illinois River Valley to the middle 20s near the Indiana border. .LONG TERM...(Monday night through Sunday) ISSUED AT 330 PM CST Sun Jan 19 2020 Temperatures will steadily warm through the middle of the week, with highs climbing back into the upper 30s to around 40 degrees by Wednesday. After that, a stronger system will come into the picture for the middle and end of the week. Models have consistently been showing a slow-moving southern stream feature spreading clouds and light precip into west-central Illinois perhaps as early as Wednesday night...with the main flux of precip holding off until Thursday night into Friday. While light snow accumulations will be possible both Wed night and Thursday night, temperatures will be too warm to support snow during the highs approach 40 on Thursday, then rise into the lower to middle 40s on Friday. End result, will be an extended period of off-and- on light precip Wednesday night through Friday night...mostly in the form of rain. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 543 PM CST Sun Jan 19 2020 MVFR cigs are in place across the central IL terminals although partial clearing is working its way southward from northern IL. This clearing is expected to reach KPIA and KBMI within an hour or two, however sites to the south are more debatable and may take several hours to see partial clearing. Additional cloudiness is likely to arrive overnight: from lake-effect from Lake Michigan at KCMI, and from a weather system dropping southward out of Manitoba. Scattered snow flurries with little or no visibility impact can be expected early this evening, and additional flurries or snow showers may impact KSPI vicinity after 17Z Monday from the approaching weather system. Winds NW 9-14 kts initially, slowly decreasing to 5-10 kts overnight. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...37 SYNOPSIS...Barnes SHORT TERM...Barnes LONG TERM...Barnes AVIATION...37
National Weather Service Jackson KY
758 PM EST Sun Jan 19 2020 .UPDATE... Issued at 758 PM EST SUN JAN 19 2020 Low stratocu is advecting in from the northwest this evening. RUC guidance has had a decent handle on these clouds, and it suggests mostly cloudy skies filling back in across eastern Kentucky through the night. Some flurries have also been noted at times in upstream observations. As such, did expand the flurries across the area. For temperatures, made some minor adjustments for this early evening update. Given that mid to upper teens are on the doorstep of the Bluegrass, wound up lowering the values a bit there. Further downstream, have bumped up some of the valley lows, as most of the ridges should be colder once again tonight, given the continued cold air advection through 850 mb, as well as the prevalent low clouds. Updates have been sent. && .SHORT TERM...(This evening through Monday night) Issued at 352 PM EST SUN JAN 19 2020 The period will be dominated by a large eastern CONUS upper trough, and large, arctic, surface high pressure`s center slowly moving from the northern plains this evening to the mid Mississippi Valley by Tuesday morning. This will keep cold air in place for our area. Steep low level lapse rates beneath a frontal inversion, coupled with just enough moisture, will result in varying amounts of clouds. They will be most prevalent over the eastern part of the area, aided by flow which came off the Great Lakes. The moisture in the mixed layer will reach into the dendritic growth zone at times, resulting in some flurries-- once again most prevalent over the eastern part of the area. A shortwave trough currently dropping out of manitoba will move south southeast in the larger scale upper level trough during the period, crossing our area Monday night. It`s main influence will be to our west, but even there any precip will be vary limited due to a lack of moisture. .LONG TERM...(Tuesday through Sunday) Issued at 302 PM EST SUN JAN 19 2020 The extended portion of the forecast begins on Tuesday with an amplified upper level pattern in place. This pattern continues to be highlighted by a stout ridge over the central Plains as this begins to shift east. This pattern allows northwest flow into the Great Lakes and the OH Valley to begin the period. The long wave trough will remain over the east for the first part of the extended but will begin to shift east as the ridge moves east into the OH Valley by Wednesday. Despite the amplitude in the pattern, features will move with some decent progression as the ridge will move east of the Appalachian Range and along the East Coast by Thursday night. This sets the stage for a transition to an active pattern as a deepening trough over the Plains crosses the MS Valley and into the lower OH Valley. The ridge however, gains some strength and builds along the East Coast. This will work to slow down the approaching trough and keeping active weather over the area for the rest of the extended. For the most part, the models have a good handle of the upper level trends with a pretty consistent run to run solution. There may be some differences in the Day 6 and Day 7 period but some confidence can be put into the model solutions. Concerning the lower level features, colder air still hanging around from the intrusion of the Arctic Airmass in northwest flow and still just enough lower level moisture will keep the chance of a few lingering flurries on Tuesday morning. After this, surface high pressure sets into place keeping mainly clear skies for the rest of the day on Tuesday and Tuesday night. The calm winds and clear skies Tuesday will allow for some 5 to 10 degree ridge to valley differences on low temperatures as some lower teens are possible in the valleys. After the morning lows, as the surface high eventually shifts east throughout the day on Wednesday allowing southerly winds and warmer temps advecting into the region and moderating the Arctic Airmass. The next chance for precip will then arrive Thursday night with the approach of the next system. The high to the east slowly giving way to the arrival may delay precip into eastern Kentucky possibly until Friday with downslope winds possible. Overnight lows into Friday morning may support a tenth of accumulation of snowfall but with downslope being a possibility, no accumulation is expected. A lack of instability seems to be the case as well so precip through much of the event seems to be stratiform. As of now, the ridge keeping the system in place over the area from Friday morning through Saturday night seems to be a long duration but QPF in total is lacking. WPC totals agree with the NBM at this time with no more than an inch over a 48 hour period in expected. No hazards are expected at this time in the extended. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) ISSUED AT 758 PM EST SUN JAN 19 2020 MVFR ceilings will build back in across eastern Kentucky through this evening from northwest to southeast. The low clouds will persist through the overnight, before gradually diminishing or raising from southwest to northeast during the day on Monday, with VFR conditions returning in the afternoon. Northwest winds of 5 to 10 kts, will veer to the north through the period. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEOGERIAN SHORT TERM...HAL LONG TERM...SHALLENBERGER AVIATION...GEOGERIAN
Area Forecast Discussion
National Weather Service Nashville TN
938 PM CST Sun Jan 19 2020 .UPDATE... FOR EVENING DISCUSSION. && .DISCUSSION... While most of the Mid State has been cloud-free today, there is a blanket of low clouds sinking south across the TN/KY state line tonight. Latest RAP soundings and model guidance suggest this cloud cover will continue to spread south overnight. Adjustments to the near-term forecast were made and temperature trends will continue to be monitored. In addition, a few flurries have been reported in Kentucky as cloud cover inches south. Very cold temperatures are accompanying this layer of clouds, so the production of a snowflake or two cannot be ruled out. However, confidence in flurries remains too low to include in this update. Cold temperatures are the top story for overnight, with values already in the upper teens and low 20s at 9 PM. For pets normally outdoors, consider bringing them inside for warmth tonight. && .AVIATION... 00Z TAF DISCUSSION. VFR. Just a few stratocumulus clouds are expected this TAF period with brisk northwest winds gradually becoming more northerly through tomorrow. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION......Schaper AVIATION........Shamburger