Aikyam-Lab/Synoptic-Bench huggingface dataset:
917 PM EDT Mon Mar 27 2017 A series of troughs will move through the area through early Tuesday and possibly trigger some showers and a few thunderstorms. A cold front will move through the area Tuesday night.
1018 PM EDT Mon Mar 27 2017 A ridge of high pressure remains stretched across the Florida Peninsula. Nestled into the base of the ridge is a nearly stationary cyclone centered northeast of Hispaniola. Temperatures are in the lower 70s with dewpoints in the mid 60s.
/Issued 310 PM CDT Mon Mar 27 2017/ Clouds continue to linger this afternoon across much of eastern Oklahoma and western Arkansas in the wake of the cold front and associated upper level low that brought showers and thunderstorms to the area yesterday into this morning.
1026 PM EDT Mon Mar 27 2017 Atlantic high pressure will weaken through Tuesday.
However, a weak Pacific cold front east of KHVR and KGTF will continue moving E'ward.
Forecast soundings indicate a weak subsidence inversion setting up across the region holding the low level moisture/clouds in place through a good portion of the day.
Ridge axis of high pressure will continue to work southward into central Florida tonight, with easterly surface winds becoming light and more variable after midnight. Isolated showers have continued to develop over the coastal waters into this evening in the low level onshore flow, and may see a stray shower or two move onto the Treasure Coast through midnight. However, model guidance indicates the low level easterly flow weakens considerably into late tonight, so potential for any additional coastal showers looks too low to mention in the forecast. (Previous Discussion) High pressure ridge extending from offshore the Carolina coast to north FL will settle into the waters while weakening.
An upper trough will cross the region tonight through Tuesday.
Upper flow is fairly zonal but wavy, but parade of upper lows continues to move across the middle of the US. At the surface, low over SE Ontario, with another over the lower Midwest. High pressure in Manitoba. Conditions for Tuesday will improve quickly in the morning as the high inches closer.
728 PM EDT Mon Mar 27 2017 Rain is expected tonight and Tuesday with crossing low pressure. Dry weather is expected with mid week high pressure before low pressure returns rain to the forecast by late week. Low pressure is progged to track from the MS Valley to the OH valley by Tuesday morning. As high pressure moves over the Great Lakes, cooler and drier air will enter the region. Even this cooler air will still be slightly above normal.
Additional cloud cover looks to develop out west and begin to spread into the region ahead of the next approaching upper level low. Slightly lower dewpoints within the weak north to easterly low level flow should allow for cooler low temperatures in the low 40s to low 50s from north to south tonight. These temperatures combined with calm/light winds and relative humidity values near 100 percent underneath high pressure could create areas of patchy fog to develop over parts of Northeast Oklahoma and Northwest Arkansas late tonight into Tuesday morning.
/issued 751 PM CDT Mon Mar 27 2017/ MVFR/IFR cigs/vsbys to return to the region overnight, as low level moisture increases ahead of an approaching trof. Frontal boundary to linger along the interstate 20 corridor through Tuesday night before lifting up as a warm front.
1047 PM CDT Mon Mar 27 2017 High pressure will be the dominant feature tonight as it extends from south central Canada through the eastern plains. But deeper moisture will then move into our area ahead of the next upper low producing increasing cloud cover from west to east. However with the continued east to southeast fetch of low level air, the lowest layers may remain a bit dry for much of our forecast area, so precip chances will erode in our western zones.
A STRONG UPPER HIGH WAS CENTERED OVER SOUTHWEST CANADA THIS EVENING AND WILL CONTINUE TO BRING WARM DRY WEATHER WITH SOME OFFSHORE FLOW TO SOUTHWEST WASHINGTON AND NORTHWEST OREGON INTO MONDAY.
535 PM MDT SUN MAY 1 2016 THE OLD LOW PRESSURE SYSTEM CENTERED OVER NE AZ WILL GRADUALLY FILL AND SLIDE EAST OVER THE NEXT 36 HOURS.
THE COLD FRONT/CONVERGENCE ZONE SITUATED ACROSS WRN TN INTO NWRN MS HAS LIT UP NEARLY STATIONARY DEEP CONVECTION, SOME OF WHICH HAS PRODUCED LANDSPOUT-TYPE FUNNEL CLOUDS. THE HIGHER CAPE AIR IN THIS ZONE MAY SHIFT WITH THE FRONT, SO HAVE KEPT CHC POPS GOING OVERNIGHT. THE CHANCES WILL INCREASE DURING THE DAY, AND PEAK DURING THE LATE AFTERNOON AND EVENING HOURS AS A WEAK COLD FRONT APPROACHES FROM THE WEST.
628 PM CDT SUN MAY 1 2016 HIGH PRESSURE WILL MOVE THROUGH THE NORTHLAND TONIGHT AND EARLY MONDAY. COULD DROP TO THE LOW 20S. AN UPPER LEVEL LOW WILL MOVE SOUTH THROUGH THE DAKOTAS LATE TONIGHT AND MONDAY. THE HIGHS SHOULD FROM THE UPPER 50S DOWNTOWN.
A cold front stretches from southern Illinois southwestward to the Gulf coast of Texas.
LOW PRESSURE IS PROGGED TO DIG RAPIDLY NEWD TODAY WITH RAIN COVERAGE INITIALLY DIMINISHING RAPIDLY WITH PROGRESS.
626 PM CDT SUN MAY 1 2016 STILL SEEING A FEW SHOWERS THIS AFTERNOON OVER THE LOWER PORTIONS OF NORTHWEST IOWA. HIGH PRESSURE BEGINS TO SETTLE INTO THE REGION TONIGHT WITH CLEARING SKIES AND DYING WINDS. THIS WILL RESULT IN A GENERALLY COOLER NIGHT. AND LOOKING AT HIGHS IN THE LOWER TO MID 60S ACROSS THE ENTIRE CWA.
/issued 343 PM CDT SUN MAY 1 2016/ (Tonight and Monday) Scattered showers and isolated thunderstorms have begun developing along and west of a Haskell to Sweetwater line as of 3 PM this afternoon, as isentropic lift from southerly flow over the top of the cool surface air mass combines with large scale lift moving in from an approaching upper level low in eastern AZ. As this low flattens out into a wave and is drawn eastward into faster westerly flow, modest lift will continue to spread into the area continuing a chance for showers and isolated storms tonight across the entire area. Cooler than normal temperatures will continue as the cool air mass will remain in place, and clouds are also expected to hang around into the afternoon hours limiting the amount of heating that the sun could provide.
A WEAKENING LOW PRESSURE SYSTEM WILL MOVE NORTH ACROSS SOUTHERN AND CENTRAL UTAH MONDAY. HIGH PRESSURE WILL BRING A WARMING TREND BEGINNING MIDWEEK. THE NEXT PACIFIC TROUGH WILL ADVANCE INTO THE GREAT BASIN LATE IN THE WEEK.
944 PM CDT SUN MAY 1 2016 STILL SEEING A FEW SHOWERS THIS AFTERNOON OVER THE LOWER PORTIONS OF NORTHWEST IOWA. HIGH PRESSURE BEGINS TO SETTLE INTO THE REGION TONIGHT WITH CLEARING SKIES AND DYING WINDS. THIS WILL RESULT IN A GENERALLY COOLER NIGHT. AND LOOKING AT HIGHS IN THE LOWER TO MID 60S ACROSS THE ENTIRE CWA.
1037 PM EDT SUN MAY 1 2016 UNSTABLE WITH COLD FRONT SINKING SOUTHEAST TONIGHT AND MONDAY.
1224 AM EDT MON MAY 2 2016 A WAVE OF LOW PRESSURE WILL SLIDE EAST ACROSS CENTRAL OHIO TONIGHT.
A REX BLOCK ALOFT /HIGH PRESSURE TO OUR NORTH AND LOW PRESSURE TO OUR SOUTH/ WILL REMAIN IN PLACE THROUGH MONDAY FOR DRY CONDITION AND MOSTLY CLEAR SKIES. GOOD RADIATIONAL COOLING TONIGHT WITH DRY AIRMASS AND LIGHT WINDS FOR TEMPERATURES IN THE LOW 40S TO UPPER 30S MONDAY MORNING.
EXPECT SHOWER ACTIVITY TO SLOWLY INCREASE THROUGH THE NIGHT AS LOW PRESSURE LOCATED IN INDIANA MOVES EAST. FARTHER SOUTH HRRR DOES NOT PREDICT A LOT OF QPF GIVEN LARGER PROXIMITY AWAY FROM THE SURFACE CYCLONE. A FAIRLY STRONG TEMPERATURE AND DEWPOINT GRADIENT IS BECOMING LESS PRONOUNCE AS THE BOUNDARY DROPS SOUTH AWAITING THE WAVE OF LOW PRESSURE. LOW PRESSURE WILL BE OVER NORTHWESTERN PENNSYLVANIA AROUND SUNRISE. WHILE RAIN WILL DIMINISH QUICKLY DURING THE MORNING WITH THE DEPARTURE OF THE LOW. A WAVE WILL DEVELOP ALONG THE TRAILING COLD FRONT.
THE COLD FRONT REMAINS ACROSS THE FAR SOUTHEAST CORNER OF THE STATE THIS EVENING. ANOTHER AREA OF RAIN ASSOCIATED WITH THE CENTER OF THE UPPER LEVEL LOW WILL TRACK ACROSS NORTHWEST AREAS. /ISSUED 659 PM CDT SUN MAY 1 2016/ A COLD FRONT REMAINS STALLED NEAR KLLQ.
900 PM EDT SUN MAY 1 2016 A FRONT WILL REMAIN STATIONARY ACROSS THE AREA THROUGH TONIGHT THEN LIFT NORTH AS A WARM FRONT MONDAY. A COLD FRONT WILL SLOWLY MOVE THROUGH MONDAY EVENING WITH MULTIPLE SURFACE WAVES MOVING ACROSS THE AREA.
AN UPPER LOW OVER SW MANITOBA WILL SLIDE INTO CENTRAL ND. WITH SOME MUCH COOLER H500 TEMPS ALOFT. THE NORTH SHOULD SEE MORE SUN AND THEREFORE SLIGHTLY WARMER TEMPS. RIDGING TRIES TO PUSH EAST ON TUE BUT EFFECTIVELY JUST TIGHTENS THE THERMAL GRADIENT FROM NORTHEAST TO SW.
733 PM EDT SUN MAY 1 2016 AVIATION A WEAK LOW PRESSURE SYSTEM MOVING ACROSS THE OHIO VALLEY TONIGHT WILL BRING RAIN SHOWERS TO SOUTHERN LOWER MICHIGAN.
UPPER LEVEL LOW ACROSS WESTERN IA IS SLOWLY LUMBERING TO THE EAST TODAY. SFC FLOW FROM THE NE LEAD TO COOLER TEMPS AND DRIER AIR ACROSS THE AREA TODAY. THE UPPER LEVEL LOW LUMBERING TO THE EAST IS THE MAIN FORECAST CONCERN FOR THE SHORT TERM. TEND TO AGREE WITH THE CAMS AND AS SUCH HAVE SLOWED ON THE PROGRESSION OF THE LOW AND RAIN LEAVING THE AREA. SLIGHTLY WARMER TEMPS AND SOME SUN RETURNS TO THE AREA. MODEL GUIDANCE SUGGESTS SYNOPTIC SCALE ASCENT LATER DURING THE PERIOD AS AN ELONGATED TROF FINALLY STARTS TO MOVE TO THE EAST AS A HIGH AMPLITUDE RIDGE BUILDS IN.
1157 PM EDT SUN MAY 1 2016 LOW PRESSURE WILL MOVE ACROSS THE AREA LATE TONIGHT AND MONDAY. SOME OF WHICH MAY BE DENSE IN THE HIGHER RIDGES. THE DAY TIME ON MONDAY WILL BE INTERESTING TO SEE IF ANY CONVECTION CAN DEVELOP AS THE COLD FRONT PUSHES TO THE SOUTH AND SOME MEAGER HEATING HAPPENS. WINDS COULD GET GUSTY /20S/ OVER THE LAURELS AS THE LOW PULLS AWAY. GENERALLY UNSETTLED WEATHER IN STORE AS A COOL UPPER LOW DROPS THROUGH MIDWEEK AND SETTLES NEAR THE MID ATLANTIC COAST FOR SEVERAL DAYS AFTER THAT.
1120 PM CDT SUN MAY 1 2016 LOW PRESSURE WILL TRACK ACROSS IOWA AND NORTHERN ILLINOIS LATE THIS AFTERNOON INTO THIS EVENING. ANY LINGERING SHOWERS WILL TAPER OFF AND END BY LATE THIS EVENING AS HIGH PRESSURE BUILDS INTO THE REGION. LOWS TONIGHT WILL RANGE FROM THE LOWER TO MID 30S ACROSS NORTH CENTRAL WISCONSIN TO THE UPPER 30S TO AROUND 40 OVER NORTHEAST IOWA.
748 PM EDT SUN MAY 1 2016 A WAVE OF LOW PRESSURE WILL SLIDE EAST ACROSS CENTRAL OHIO TONIGHT.
1136 PM EDT SUN MAY 1 2016 AVIATION A WEAK LOW PRESSURE SYSTEM MOVING ACROSS THE OHIO VALLEY TONIGHT WILL BRING RAIN SHOWERS TO SOUTHERN LOWER MICHIGAN.
KEPT A 50 TO 60 PERCENT CHANCE OF RAIN ALONG AND EAST OF THE HIGHWAY 59 CORRIDOR FOR THE OVERNIGHT PERIOD. COLD FRONT SHOULD MOVE THROUGH IN THE MORNING WITH LINGERING SHOWERS.
MVFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH MONDAY MORNING DUE TO SCATTERED CONVECTION FROM THE NW AHEAD A COLD FRONT. WINDS WILL BECOME NORTHWEST MONDAY AFTN AND EVNG IN THE WAKE OF THE COLD FRONT. THERE ALSO SEEMS TO BE AN INVERTED TROUGH AXIS/BOUNDARY/MOISTURE CONVERGENCE TO THE OVER CENTRAL/WEST LOUISIANA. RIGHT NOW IT LOOKS LIKE THE LOW PRESSURE SYSTEM/FRONT WILL FINALLY START TO MOVE EAST EARLY MONDAY. THE NEXT CUT OFF LOW MOVES INTO THE WEST COAST FORCING THE UPPER TROUGH OVER THE GREAT LAKES TO MOVE EAST.
746 PM EDT SUN MAY 1 2016 WAVES OF LOW PRESSURE TRAVELING ALONG A SLOW MOVING FRONTAL BOUNDARY WILL TRIGGER NUMEROUS SHOWERS AND THUNDERSTORMS THIS EVENING INTO TONIGHT. ANOTHER WAVE OF LOW PRESSURE IS FORECAST TO BRING MORE SHOWERS AND A FEW THUNDERSTORMS PRIMARILY TO SOUTHERN LOCATIONS ON MONDAY.
AFTER MIDNIGHT AND CLOSER TO DAYBREAK CHANCES SHOULD INCREASE AS A WEAK AREA OF LOW PRESSURE OVER THE LOWER MISSIPPI RIVER VALLEY TRACKS ACROSS THE MID-SOUTH.
1042 PM EDT SUN MAY 1 2016 LOW PRESSURE WILL MOVE ACROSS THE AREA LATE TONIGHT AND MONDAY. SOME OF WHICH MAY BE DENSE IN THE HIGHER RIDGES. THE DAY TIME ON MONDAY WILL BE INTERESTING TO SEE IF ANY CONVECTION CAN DEVELOP AS THE COLD FRONT PUSHES TO THE SOUTH AND SOME MEAGER HEATING HAPPENS. WINDS COULD GET GUSTY /20S/ OVER THE LAURELS AS THE LOW PULLS AWAY. GENERALLY UNSETTLED WEATHER IN STORE AS A COOL UPPER LOW DROPS THROUGH MIDWEEK AND SETTLES NEAR THE MID ATLANTIC COAST FOR SEVERAL DAYS AFTER THAT.
743 PM EDT SUN MAY 1 2016 UNSTABLE WITH COLD FRONT SINKING SOUTHEAST TONIGHT AND MONDAY.
855 PM MDT SUN MAY 1 2016 QUIET/DRY WEATHER IN STORE FOR OUR CWA TONIGHT AS WE REMAIN LARGELY DOMINATED BY STRONG RIDGE OVER SOUTHERN BC/SASKATCHEWAN. A PV MAX ON THE EASTERN EDGE OF THIS RIDGE IN SOUTHERN CANADA IS SPREADING INCREASED HIGH CLOUDS TO NORTHEAST MT THIS EVENING.
1124 PM CDT SUN MAY 1 2016 Clouds will continue to move southeast and will overspread the area by mid evening as upper trough back over eastern Nebraska drops southeast into Missouri and Illinois. Some isolated showers may begin to develop toward morning underneath the upper trough over central and northeast Missouri.
WHICH IS NEAR THE FREEZING LEVEL. THE THREAT OF HEAVY RAIN SHOULD START TO ABATE MONDAY NIGHT AS A COLD FRONT SLOWLY MOVES THROUGH SOUTHEAST LOUISIANA AND SOUTH MISSISSIPPI.
CURRENT THINKING IS THAT THE HIGH CLOUDS ASSOCIATED WITH CONVECTION NEAR THE LOUISIANA GULF COAST AND THE EXPECTED DEVELOPMENT OF LOW STRATUS DUE TO LOW-LEVEL MOIST ISENTROPIC LIFT WILL BE LIMITING FACTORS KEEPING FOG FROM BEING WIDESPREAD. WITH LIGHT WINDS WILL ALSO HAVE TO MONITOR FOR POSSIBLE LIGHT FOG DEVELOPMENT PRIOR TO THE LOW CLOUDS DEVELOPING. BUT THIS WILL BE CONTINGENT ON ENOUGH CLEARING FROM THE HIGH CLOUDS STREAMING ACROSS THE AREA.
BRISK ZONAL COMPONENT TO THE H50-H10 FLOW OVER THE SRN TIER STATES WILL NUDGE THE RIDGE AXIS OVER THE W ATLC TOWARD BERMUDA. THE RIDGE WILL MAINTAIN THE SERLY H100-H70 FLOW THAT HAS PERSISTED FOR THE PAST FEW DAYS. THIS LOW LVL FLOW WILL BEGIN TO TAP A SLUG OF SUBTROPICAL MOISTURE ENCROACHING ON THE SRN BAHAMAS. WITH THE RIDGE AXIS DRIFTING SEAWARD.
824 PM EDT SUN MAY 1 2016 LOW PRESSURE WILL MOVE ACROSS THE AREA LATE TONIGHT AND MONDAY. A SIGNIFICANT SHORT WAVE TROUGH/ VORT MAX IS ASSOCIATED WITH THIS POSSIBLE MCS. THE DAY TIME ON MONDAY WILL BE INTERESTING TO SEE IF ANY CONVECTION CAN DEVELOP AS THE COLD FRONT PUSHES TO THE SOUTH AND SOME MEAGER HEATING HAPPENS. WINDS COULD GET GUSTY /20S/ OVER THE LAURELS AS THE LOW PULLS AWAY. GENERALLY UNSETTLED WEATHER IN STORE AS A COOL UPPER LOW DROPS THROUGH MIDWEEK AND SETTLES NEAR THE MID ATLANTIC COAST FOR SEVERAL DAYS AFTER THAT.
906 PM PDT SUN MAY 1 2016 A departing low pressure system will bring isolated showers and thunderstorms through late this evening across interior areas.
539 PM PDT SUN MAY 1 2016 Updated Aviation section A departing low pressure system will bring the slight chance of showers and thunderstorms through this evening across interior areas.
THE COLD FRONT/CONVERGENCE ZONE SITUATED ACROSS WRN TN INTO NWRN MS HAS LIT UP NEARLY STATIONARY DEEP CONVECTION, SOME OF WHICH HAS PRODUCED LANDSPOUT-TYPE FUNNEL CLOUDS. THE HIGHER CAPE AIR IN THIS ZONE MAY SHIFT WITH THE FRONT, SO HAVE KEPT CHC POPS GOING OVERNIGHT.
534 PM MDT SUN MAY 1 2016 00Z TAF CYCLE UPPER LOW OVER EAST CENTRAL AZ AT 23Z TO SLOWLY WEAKEN AND DISSIPATE AFT 06Z. AS A WEAKENING UPPER LEVEL LOW PRESSURE SYSTEM CROSSES NORTHERN NEW MEXICO. IN ITS WAKE A RESIDUAL UPPER LEVEL TROUGH WILL LINGER OVER THE AREA AND WORK WITH RECYCLED MOISTURE TO PRODUCE SHOWERS AND THUNDERSTORMS FAVORING NORTH CENTRAL TO WEST CENTRAL AREAS ON MONDAY AND MONDAY NIGHT.
100 AM EDT MON MAY 2 2016 LOW PRESSURE WILL APPROACH FROM THE SOUTHWEST TONIGHT AND WILL SLOWLY CROSS THE REGION MONDAY THROUGH MONDAY NIGHT.
659 PM CDT SUN MAY 1 2016 A COLD FRONT REMAINS STALLED NEAR KLLQ.
751 PM EDT SUN MAY 1 2016 A MOIST SOUTHERLY FLOW WILL CONTINUE INTO THE FORECAST AREA THROUGH MONDAY AHEAD OF A SLOW MOVING COLD FRONT.
COLD FRONT SHOULD MOVE THROUGH IN THE MORNING WITH LINGERING SHOWERS.
CHATTANOOGA AIRPORT, TN 63 78 60 72 / 50 80 70 30 KNOXVILLE MCGHEE TYSON AIRPORT, TN 63 75 58 71 / 50 70 70 40 OAK RIDGE, TN 63 74 59 70 / 50 80 60 30 TRI CITIES AIRPORT, TN 59 74 57 70 / 50 70 70 40.
SEABREEZES MOVED INLAND TODAY BUT LITTLE CONVECTION OCCURRED OVER NE FL DUE TO SUBSIDENCE/DRY AIR ASSOCIATED WITH MID LEVEL RIDGING.
926 PM EDT SUN MAY 1 2016 WAVES OF LOW PRESSURE TRAVELING ALONG A SLOW MOVING FRONTAL BOUNDARY WILL TRIGGER NUMEROUS SHOWERS AND THUNDERSTORMS TONIGHT. ANOTHER WAVE OF LOW PRESSURE IS FORECAST TO BRING MORE SHOWERS AND A FEW THUNDERSTORMS PRIMARILY TO SOUTHERN LOCATIONS ON MONDAY.
1012 PM EDT SUN MAY 1 2016 A MOIST SOUTHERLY FLOW WILL CONTINUE INTO THE FORECAST AREA THROUGH MONDAY AHEAD OF A SLOW MOVING COLD FRONT.
921 PM EDT SUN MAY 1 2016 A WAVE OF LOW PRESSURE WILL SLIDE EAST ACROSS CENTRAL OHIO TONIGHT.
945 PM EDT SUN MAY 1 2016 LOW PRESSURE WILL APPROACH FROM THE SOUTHWEST TONIGHT AND WILL SLOWLY CROSS THE REGION MONDAY THROUGH MONDAY NIGHT.
AM EXPECTING THAT THE COLD FRONT MOVG THROUGH S TX WILL CONVERGE WITH WHAT IS LEFT OF THE SEA BREEZE TO PRODUCE SCT CONVECTION OVERNIGHT. ONCE THE COOLER/DRIER NEAR SFC SHALLOW AIRMASS UNDERCUTS THE STORMS. WEAK/STALLING COLD FRONT IS STILL DRAPED ACROSS OUR NORTHERN ZONES AT THIS HOUR.
746 PM EDT SUN MAY 22 2016 Weak low pressure along the Carolina coast will move slowly northeast. otherwise dry high pressure will build into the region through midweek. A closed upper level low will continue to drop south into the Mid-Atlantic region. A mid level short wave trough rotating around the upper low will move across the Midlands tonight. Upper level low along the North Carolina coast Monday. Upper ridge in the midwest moving slowly east.
/issued 209 PM CDT SUN MAY 22 2016/ Oklahoma and the southern plains are now under the influence of the large upper trough over the western U.
1051 PM MDT SUN MAY 22 2016 H5 hand analysis at 12z had a dominant ridge over the central CONUS with low pressure systems along both right and left coastal states. Our CWA is squeezed between the ridge and west coast low leaving moderately fast southwest flow aloft. but at ridge tops and near showers gusty winds will continue into the evening. Downstream blocking over the eastern states over the next 24 to 36 hours leaves low pressure over the northern rockies and intermountain west. 5 PVU progs suggest another wave passing through Monday afternoon during peak heating and will lead to another round of convection over the higher terrain over the northern mountains. Temperatures will be slightly warmer on Monday but stay below normal for this time of May.
534 PM MDT SUN MAY 22 2016 AVIATION SECTION UPDATED A strong upper level low is spinning just north of our forecast area, and slowly drifting northeast into Saskatchewan. Deep moisture wrapping around the west side of the upper low is producing record rainfall, per NWS MSO, at some locations west of the Continental Divide.
An elongated upper level trough stretching from southern Canada to the California coast will maintain a mostly dry and mild southwest flow over Utah early in the week. Cool and unsettled conditions will return midweek as the trough shifts east through the Great Basin. Water Vapor loop shows an expansive trough firmly in place across the Western CONUS. even in the higher terrain Monday afternoon.
516 PM MDT SUN MAY 22 2016 H5 hand analysis at 12z had a dominant ridge over the central CONUS with low pressure systems along both right and left coastal states. Our CWA is squeezed between the ridge and west coast low leaving moderately fast southwest flow aloft. but at ridge tops and near showers gusty winds will continue into the evening. Downstream blocking over the eastern states over the next 24 to 36 hours leaves low pressure over the northern rockies and intermountain west. 5 PVU progs suggest another wave passing through Monday afternoon during peak heating and will lead to another round of convection over the higher terrain over the northern mountains. Temperatures will be slightly warmer on Monday but stay below normal for this time of May.
905 PM EDT SUN MAY 22 2016 Update A ridge of high pressure will continue to dominate the weather pattern through Monday and result in mostly clear skies.
603 PM CDT SUN MAY 22 2016 An upper-level ridge over the region will continue to provide for ideal conditions the remainder of the day before a persistent unsettled pattern arrives tomorrow. Temperatures will climb to the low 80s this afternoon as surface flow transitions out of the south. This southerly surface flow will advect moisture into the region throughout the week as dewpoints currently in the upper 50s rise into the lower 70s by the mid week. The low-level jet over central Kansas will slowly push eastward early Monday morning and the area within this flow will be the focus for the first of many rounds of thunderstorms beginning Monday. This activity will be maintained coincident with the low- level jet, along a SW to NE axis mostly west of I-35 before expanding eastward into the afternoon and evening hours.
BMickelson Previous short term discussion: Cooler weather will continue with the presence of a persisting upper trough over the region through the midweek. A large-scale general or overall trough stretches over the western states and the high plains regions. This predominance of some version of low pressure influence will simply add to the multiple forecast periods of northeast Montana not quite being free from the threat of precipitation.
A few of of the high res models bring in convective remains from the west in the afternoon but they may not survive to IAH/HOU.
With the main upper low center well to the northeast, shower activity will dissipate across southeast Oregon and most of southwest Idaho overnight as the atmosphere stabilizes. Scattered showers and isolated thunderstorms will end by 06z, then redevelop over the higher terrain on Monday, mainly after 18z.
Model soundings suggest the low levels will be a bit too dry for fog since dewpoints did drop into the 40s earlier today.
Sunny skies and light winds are providing a tranquil summer day to the area today, with most locations in the lower 80s as of 2 pm. Dewpoints in the lower to mid 40s are creating humidity levels of 20 to 30 %. The high pressure overhead will keep clear and quiet conditions in place tonight, and will linger Monday with increasing south winds and high clouds. Lows tonight will likely be a few degrees warmer than night, as modification continues.
For 06Z TAFs: High pressure across region will provide for VFR conditions for both KMSL and KHSV thru the fcst period.
Plenty of moisture continues to surge in ahead of gradually progressing cold front (dewpoints in the lower 60s) to bring the risk of heavy rainfall from some storms. Severe thunderstorms highlight the short term period The latest water vapor imagery shows a closed low circulating over Alberta with a 100kt jet streak stretched out from northeast Montana into central Wyoming. This will provide large scale ascent along a cold frontal boundary, now located from Portal to Stanley, and south into Hettinger. Dewpoints in the west are in the lower 40s while in central North Dakota moisture is higher with dewpoints near 60F. The cold front will slowly move east tonight, exiting the James River Valley between 09z-12z Monday. Broad trough over the western CONUS gradually works eastward towards the plains through the middle and end of the upcoming week.
/issued 342 PM CDT SUN MAY 22 2016/ (Tonight and Monday) An upper ridge extends from Texas north-northeast into the upper Mississippi Valley, with the ridge axis shifting slowly east of our area this afternoon. The overall setup on Monday looks similar to today with southwest flow over our area, but the upper ridge axis will be a little farther east.
651 PM CDT SUN MAY 22 2016 A high pressure ridge over the Mississippi River Valley this afternoon will continue to move across the region tonight. The ridge will keep the skies mostly clear with very light and variable winds. By morning, the ridge axis should be much further to the east, resulting in more south/southeasterly turn to the winds. Two upper lows, over the east and west coast remain in place today. with pleasant weather in the middle and warm temperatures continuing to build a thermal ridge in the mid levels over the Plains.
Upper low pressure area along the mid atlantic coast is slowly rotating counterclockwise and bring in more showers and a few thunderstorms across NE TN and SW VA this evening.
913 PM EDT SUN MAY 22 2016 Upper level low lingers around the mid Atlantic states into Monday.