Aikyam-Lab/Synoptic-Bench huggingface dataset:
isolated, small showers this morning south of the Golden Gate Bridge. An upper low centered over interior NorCal allowed for additional showers overnight. The hi-res NAM and HRRR indicate that these small, cellular showers should persist for the mentioned areas this morning and then dissipate by late afternoon as the center of the upper low tracks SE into southern Nevada. Expect colder valley areas to continue dropping into the low to mid 30s with isolated areas of frost.
Cooler temperatures to start work week. Slightly warmer on Wed/Thu ahead of next front. This evening/tonight, the cold front will move into the central/southern MO Ozarks, but might not quite make it all the way through, stalling from southeast OK to the southeast MO Bootheel and OH Vly by daybreak Sunday.
540 DM upper low centered near KRNO this morning is progged to move down the Sierra Nevada, pushing into southern Nevada this afternoon. Heights begin to rise over interior NorCal tonight into Sunday as EPAC upper ridge begins to build inland with northerly flow aloft. Areas of frost possible in the Central Valley tonight as skies clear, dewpoints lower, and longwave radiational cooling drops the mercury into the low to mid 30s.
425 AM PST Sat Mar 5 2022 Cold low pressure centered near Lake Tahoe this morning is pivoting an inverted trough from east to west/counterclockwise, across Northern California and southwestern Oregon this morning. The inverted trough is combining with the terrain this current hour causing some enhancement to the snowfall along the Modoc Plateau, across Lava Beds National Monument, the Medicine Lake area, and from Tennant and MacDoel across the north side of Mount Shasta to the Weed, CA area.
238 AM MST Sat Mar 5 2022 A series of weather systems will bring gusty winds over the weekend along with cooler temperatures. A broader trough has set up over the Great Basin and intermountain west.
740 AM EST Sat Mar 5 2022 Dry, warm weather will prevail today under high pressure. Rain and gusty wind is expected Sunday with approaching low pressure. Mid and upper level clouds are in place over the region, ahead of a ridge over the Lower Ohio Valley and Great Lakes. The ridge will cross the region this afternoon, along with a warm front, leading to a temporary decrease in cloud coverage this afternoon. Above average temps are expected to continue overnight under strong warm, moist advection as a low pressure system strengthens and advances into the Great Lakes. Pre-frontal, scattered rain showers are likely to be observed early Sunday morning as the trough passes over Lake Erie and quickly enters the New England region.
A few lingering snow showers are expected mainly in the upslope areas of the high terrain through the afternoon, specifically along the Mogollon Rim, Chuska and White Mountains. Afternoon wind gusts 30-40 kts are expected over the high terrain, with strong gusts possible in the Little Colorado River Valley immediately downwind of the Mogollon Rim.
437 AM MST Sat Mar 5 2022 The latest upper analysis shows a complicated setup with the main upper trough extending from a relatively weak upper low over Saskatchewan to the main/stronger upper low over California and Nevada. There is another, weaker, upper trough/low center currently over Colorado that will bring wintry precipitation t our forecast area as it moves northeastward into Nebraska and South Dakota today. Precipitation will continue to spread across much of the forecast area today, gradually ending from west to east later this afternoon as the low pressure system moves away from the forecast area.
In the upper levels, upper ridging was centered over the western Gulf of Mexico. A surface front was located in the high Plains. Low pressure will drag the front further southward through Sunday. During the overnight, the upper ridge will begin to shift eastward. At the same time, low pressure will drag the cold front east/southeastward into the remainder of Arkansas, with additional showers/storms along the boundary.
244 AM MST Sat Mar 5 2022 The latest upper analysis shows a complicated setup with the main upper trough extending from a relatively weak upper low over Saskatchewan to the main/stronger upper low over California and Nevada. There is another, weaker, upper trough/low center currently over Colorado that will bring wintry precipitation t our forecast area as it moves northeastward into Nebraska and South Dakota today. Precipitation will continue to spread across much of the forecast area today, gradually ending from west to east later this afternoon as the low pressure system moves away from the forecast area.
A closed low is currently centered along the northern CA and NV border, with moist and unstable air spreading up into much of northern and central NV.
438 AM MST Sat Mar 5 2022 Wave moving into the Dakotas this morning, with an area of high pressure pushing south from Alberta. Snow will taper off by the afternoon as the high pressure spreads east. This high will linger across the region through Sunday.
All of the ensemble members show at least a cooler with increased chance for snow this week, but as shown above, there is uncertainty in how cold and how snowy it will be.
Surface analysis depicts a sprawling area of high pressure centered just east of Delaware and covering the entire Eastern Seaboard, with the Keys lying in a tight pressure gradient along the southern periphery of this high. Aloft, a deep ridge centered over the southern Gulf of Mexico continues to dominate our region.
633 AM EST Sat Mar 5 2022 An upper-level ridge will build over the forecast area on Saturday paving the way to the warmest days of the year thus far.
Weak surface convergence was occurring here with surface observations and satellite fog probability product indicating stratus/fog over western and south central ND and this is likely where any significant freezing drizzle remains. Think the freezing drizzle potential here is very low. Thus this area looks to be the most likely to see lingering freezing drizzle. By midday today the threat of freezing drizzle should be just about over, and any remaining light precipitation will be snow. Lows tonight will range from around 5 above northwest to the lower teens southeast.
621 AM EST Sat Mar 5 2022 Dry, warm weather will prevail today under high pressure. Rain is expected Sunday with approaching low pressure. Dry, quiet weather is expected today under high pressure. Above average temps are expected to continue overnight under strong warm, moist advection as a low pressure system strengthens and advances into the Great Lakes. Pre-frontal, scattered rain showers are likely to be observed early Sunday morning as the trough passes over Lake Erie and quickly enters the New England region.
High Pressure currently positioned just off the Mid-Atlantic coast will gradually move further out to sea through Sunday, fostering breezy easterly flow over SFL on its southern flank. Aloft, robust H5 ridging will build NEwrd over the area supporting dynamic subsidence and maintaining mostly dry conditions. As mentioned in previous discussions temperatures will be typical of an easterly regime with warmer highs over the west coast/interior (the synoptic gradient should be strong enough to inhibit Gulf Breeze progression), and warmer lows over the east coast.
525 AM EST Sat Mar 5 2022 Dry, warm weather will prevail today under high pressure. Rain is expected Sunday with approaching low pressure. Dry, quiet weather is expected today under high pressure. Above average temps are expected to continue overnight under strong warm, moist advection as a low pressure system strengthens and advances into the Great Lakes. Pre-frontal, scattered rain showers are likely to be observed early Sunday morning as the trough passes over Lake Erie and quickly enters the New England region.
Sunday will remain on the chilly side with highs struggling to make it out of the lower 39s.
To our southwest, upper low remains centered near Lake Tahoe and this feature will shift east across central Nevada throughout the day. As the low moves towards the Four Corners, global guidance as well as hi-res models depict a decent band of snow in the SE corner of the state and this appear to be the primary area of heaviest snowfall accumulations with this system late Saturday into the first half of the day Sunday. After coordination with surrounding WFOs decided to issue a Winter Weather Advisory across the SE corner where the highest accumulations should be.
105 PM EST Sat Mar 5 2022 Dry, warm weather will prevail today under high pressure. Rain and gusty wind is expected Sunday with approaching low pressure. Mid and upper level clouds are in place over the region, ahead of a ridge over the Lower Ohio Valley and Great Lakes. The ridge will cross the region this afternoon, along with a warm front, leading to a temporary decrease in cloud coverage this afternoon. Above average temps are expected to continue overnight under strong warm, moist advection as a low pressure system strengthens and advances into the Great Lakes. Pre-frontal, scattered rain showers are likely to be observed early Sunday morning as the trough passes over Lake Erie and quickly enters the New England region.
This is a result of a low pressure system moving over the Midwest, Great Lakes, and up into Canada during this time.
It will make it as far southeast as our far northwestern corner on Sunday morning before retreating northward as a warm front.
An upper level low/trough across the Four Corners region Sunday morning, will track east toward eastern New Mexico/Colorado late in the day Sunday. Meanwhile a cold front will move into the northern Big Country Sunday morning, then stall across the Big Country through the day. Trended temperatures behind the cold front down some, across the Big Country, but these numbers may need to eventually need to be trended down even more. The highest temperatures look to be across the Concho Valley, where highs in the 80s are forecast, with slightly cooler temperatures in our southeast counties, where cloud cover is forecast to linger through early to mid afternoon. (Sunday night through next Saturday) The cold front will push south across the area Sunday night, bringing much cooler temperatures through the early part of the week.
350 PM EST Sat Mar 5 2022 A warm front continues to slide north of the area tonight allowing for a warm night with deep south to southwest flow.
An upper level low/trough across the Four Corners region Sunday morning, will track east toward eastern New Mexico/Colorado late in the day Sunday. Meanwhile a cold front will move into the northern Big Country Sunday morning, then stall across the Big Country through the day. Trended temperatures behind the cold front down some, across the Big Country, but these numbers may need to eventually need to be trended down even more. The highest temperatures look to be across the Concho Valley, where highs in the 80s are forecast, with slightly cooler temperatures in our southeast counties, where cloud cover is forecast to linger through early to mid afternoon.
258 PM CST Sat Mar 5 2022 This morningâs cold front pushed through faster than expected, resulting in a significantly colder day for most of the area. Fortunately, road temperatures are still above freezing across most of the area, but northern portions of the area have seen significant ice accretion (ODX ASOS reported 0. This threat is most prevalent in the advisory area where air temps are already at or below freezing, but some slick spots are possible across the rest of central Nebraska as temperatures fall late this afternoon.
(The rest of today ) A strong upper low pressure system was centered over western KS this morning, lifting northeast. At the surface, low pressure was approaching Concordia KS, with a Pacific front/dryline extending south of the low across far western OK.
Only widely scattered showers are expected this evening into early tonight and lows fall into the lower to middle 60s F. A strong upper ridge will largely be in control and that will also contribute to subsidence or at best minimal upper level forcing for ascent.
There's been a mix of freezing precip(drizzle/rain) in some of our western zones and points just to the west outside of our CWA to plain snowfall across western and extreme south-central SD. Freezing precip will remain possible into early afternoon, but should become mostly snow after that. Again, some pockets of a mix or freezing precip still are possible before turning to all snow by this evening. First, we have northerly flow across north central South Dakota, with lower ceilings and dewpoint depressions suggesting freezing drizzle is in fact possible if not occurring up that way, however across the eastern CWA while we do have status in place, upstream dewpoints in the single digits/teens are resulting in drier subcloud layers and thus eastern South Dakota remains dry.
Showers and thunderstorms are occurring within the warm sector across eastern NE into Iowa with our snow occurring on the northern edge of the low-to-mid-level baroclinic zone. As the upper trough axis pivots east of the forecast area and the system lifts northeastward, snow will taper off from NW to SE later this afternoon and evening. Looking further upstream, a closed upper low churns across south-central CA/southern NV while another upper trough axis is centered over southern Saskatchewan. The broad, large scale upper trough will linger across the western and central part of the US to start the week.
Water vapor imagery highlights strong anticylonic flow across the eastern third of the CONUS, with high pressure centered just off the Mid Atlantic coastline. There continues to be a significant north to south moisture gradient, with dry subsidence associated with the ridge to the north across much of the Florida Mainland butting up against much more moist lower-levels to the south.
1051 AM MST Sat Mar 5 2022 The latest upper analysis shows a complicated setup with the main upper trough extending from a relatively weak upper low over Saskatchewan to the main/stronger upper low over California and Nevada. There is another, weaker, upper trough/low center currently over Colorado that will bring wintry precipitation t our forecast area as it moves northeastward into Nebraska and South Dakota today. Precipitation will continue to spread across much of the forecast area today, gradually ending from west to east later this afternoon as the low pressure system moves away from the forecast area.
As a cold front/northerly wind shift advances southward from Kansas this afternoon/evening, cooler temperatures and higher dew points will result in improving relative humidity and fire weather conditions. , freezing rain or sleet) across west-central/northwest Oklahoma during the onset. However, the more likely scenario is temperatures will warm above freezing before precipitation begins (i. Strong to severe thunderstorms may develop ahead of the cold front (in the warm sector) across southeast Oklahoma tomorrow afternoon.
The weather will also remain dry over South Florida through Sunday as drier in the lower levels of the atmosphere has work into the region from the Atlantic waters. Temperatures tonight will be running about 10 degrees warmer than average for the east coast metro areas with lower to mid 70s due to the breezy to windy easterly winds. Rest of South Florida will be running about 5 to 10 degrees warmer in the 60s.
1147 AM CST Sat Mar 5 2022 (The rest of today ) A strong upper low pressure system was centered over western KS this morning, lifting northeast. At the surface, low pressure was approaching Concordia KS, with a Pacific front/dryline extending south of the low across far western OK.
Did not make any changes to temperatures at this point as expect temperatures to still climb into the lower 70s to possibly near 80 degrees despite the increase in cloud cover due to warm air advection that is occurring. /issued 420 AM CST Sat Mar 5 2022/ Surface analysis early this morning places a cold front over the Northern Plains while a ridge of high pressure is located near Florida. Southerly winds on the back side of high pressure is continuing to bring mild temperatures to the Mid- South this morning. Short term models including some Convective Allowing Model solutions indicate a potential for perhaps a few warm advection rain showers mainly along and west of the Mississippi River this afternoon but think most areas may remain dry given the lower dewpoint air in place across the area.
At the surface, a north south oriented trough was serving as focus for band of light snow, generally extending from the International Border north northeast of Minot, to just west of Bismarck/Mandan, and then down to around Hettinger. Highs will be similar as today, but cooler across portions of the north and east where cloud cover will remain in tact through much of the day. Highs will range from the mid to upper teens north, to the lower 20s over the James River Valley, and the mid to upper 20s southwest and south central.
For the rest of the day, breezy conditions, especially along the Treasure Coast, with a tight pressure gradient in place from strong high pressure over the Atlantic. It will be warm, with temperatures in the low to mid-80s. Increased E/SE winds today, with a tight pressure gradient across the area from high pressure over the Atlantic.
---BMickelson Previous discussion: Wave moving into the Dakotas this morning, with an area of high pressure pushing south from Alberta. Snow will taper off by the afternoon as the high pressure spreads east. This high will linger across the region through Sunday.
A dry and cool northerly flow is setting up over the region this morning as an upper low continues to dig south towards the desert southwest. Breezy northerly winds will develop across portions of central OR and the Ochoco-John Day Highlands as the upper low clips southern OR and northern NV this afternoon, with light winds elsewhere.
The first will be with the convection ahead of the cold front. The second will be near and behind the cold frontal passage. So, the midnight to 100pm time frame of the High Wind Warning will cover both surges of wind. The strongest and most widespread wind looks to be right near the cold front which will be sliding through especially between 500am and 700am. In terms of the threat of severe thunderstorms, the main threat will be wind and that will already be covered by the High Wind Warning which mentions wind gusts to around 60 mph.
A very strong cold front continues to creep south across our far southeastern counties with about a 30 degree change from the north to the south side of the boundary. Verification across portions of northeast Nebraska indicated patchy areas of both sleet and freezing rain. Drier and cooler conditions are expected for Sunday with highs only in the 30s and 40s.
(Through tonight ) Red Flag Warning will remain in effect until 8 PM as dangerous fire weather potential will develop across parts of northeast OK over the next few hours with the passage of a dry line, followed later this evening by a cold front. Cold front will gradually push south overnight and should extend near a MLC-FYV line by 12z Sunday.
1049 AM EST Sat Mar 5 2022 An upper-level ridge will build over the forecast area on Saturday paving the way to the warmest days of the year thus far.
226 PM CST Sat Mar 5 2022 After very brief short wave ridging overhead this evening a short wave trough will approach the area on Sunday setting up a critical fire weather day. This speed max will be juxtaposed with a low level thermal ridge on the caprock during the afternoon before moving east.
137 PM EST Sat Mar 5 2022 An upper-level ridge will build over the forecast area today paving the way to the warmest days of the year thus far.
A upper level trough will dive south from Canada after 06/0600, with light snow showers developing across northwest Montana soon thereafter. A polar air mass infiltrated western Montana last night and has resulted in slightly cooler temperatures this afternoon. The cooler air mass didnât make it over into north-central Idaho where Pierce is sitting at 51 degrees as of 1 pm PST.
426 PM MST Sat Mar 5 2022 Snowfall has been slowly dwindling down this afternoon as the initial upper level low continues to push off to the north and east. However, the upper low still looks to be positioned farther south than today's system limiting support for lift and higher snowfall rates.
Otherwise, a mix of sun and clouds persist over the region this afternoon with temperatures warming only into the low/mid 50s. As the aforementioned mid/upper level low exits to the east tonight, winds will diminish and sky conditions will begin to clear. However, widespread freezing conditions are not likely outside of the coldest interior valleys. Sunday will feature mostly sunny conditions with daytime temperatures reaching into the low/mid 60s. A gradual warming trend is then anticipated heading into the upcoming week as high pressure builds over the eastern Pacific. KSFO Bridge Approach.
Remaining snow in north central Nebraska will begin to taper off in the evening as the low pressure system tracks east out of the forecast area. Although skies will remain cloudy overnight, fresh snowpack is expected to maintain cooler overnight temperatures, so used NBM 25th percentile for overnight lows. Tomorrow, the upper level trough will slide east into the Great Plains, giving support for the next opportunity for precipitation. A broad upper level trough will extend south into North America during the week, leading to below normal temperatures.
(The rest of tonight) Cold front has pushed southeast to just north of I-44 this evening. Only a narrow corridor of lower RH remains and values will continue to recover this evening as cold front overtakes dry line. Latest CAMs/radar indicate narrow line of thunderstorms along cold front will likely remain just north of CWA this evening, but will continue to monitor.
238 PM MST Sat Mar 5 2022 Snowfall has been slowly dwindling down this afternoon as the initial upper level low continues to push off to the north and east. However, the upper low still looks to be positioned farther south than today's system limiting support for lift and higher snowfall rates.
Scattered showers continue this afternoon on the back side of an upper low sliding southeast along the California-Nevada border. With cooler air in place and cloudy skies, highs this afternoon are on track to top out around 8-12 degrees below climo. The High resolution models also maintain the gusty winds in the Kern County mountain and desert areas through late this evening and the Wind Advisory remains in effect there through midnight tonight. Models continue to move the low pressure system out tonight and drop a weak impulse through the Great Basin region Sunday.
Snowfall has been slowly dwindling down this afternoon as the initial upper level low continues to push off to the north and east. However, the upper low still looks to be positioned farther south than today's system limiting support for lift and higher snowfall rates.
Highlights/Key Points: -- Temperatures today have been colder than anticipated as the low pressure tracked further to the southeast, taking the severe threat with it. Details: This Evening/Tonight: Low pressure centered over southern NE/southern IA will continue to lift off to the north and east. Ahead of the snow band, a mix of rain, freezing rain, and sleet continues until temperatures fall both at the surface and aloft to maintain ice.
Upper air analysis shows a longwave trough over much of North America from central Canada into the western CONUS. This system was pushing a cold front through the forecast area today and by mid afternoon the front was moving through south central Kansas.