Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/26/17

Area Forecast Discussion
National Weather Service Gaylord MI
1044 PM EDT Thu May 25 2017 .UPDATE... Issued at 921 PM EDT Thu May 25 2017 Moisture continues to pinwheel back west into northern Michigan. Just enough forcing to keep areas of drizzle and very light showers, especially across northeast lower Michigan. Trend through tonight should be for less precip with time, and what there is becoming increasingly confined to areas east of interstate 75. Low clouds, however, look much more stubborn to yield, and may actually see them fill back in where some breaks in the overcast currently reside. Likely to see some patchy fog as winds slacken. Will need to monitor this potential with some guidance suggesting more aggressive fog development than currently depicted in the forecast. && .NEAR TERM...(Tonight through Friday) Issued at 254 PM EDT Thu May 25 2017 ...Somewhat improving wx to wrap up the work week... High impact weather potential...none. Surface low in n-central Ohio continues to move slowly ne. Some associated moisture continues to push back into northern MI from the e, resulting in generally light precip over central and eastern sections. We`re already on the far west edge of this system, and as it continues to pull out to the ne, our wx will improve. Somewhat. Tonight/Friday...secondary development over the ne states will contribute to the diminishing influence of the present Ohio low. But a lobe of deeper moisture will hang back across Lake Huron and surroundings, only really washing out Friday morning. Even then, the window between that departing, and developing warm advection cloud cover ahead of a low in s central Canada, will be small. It does not seem likely that we will see the unrelenting sunshine places west of Lake MI are enjoying today. Models differ somewhat as to how long the grunge will linger. Most recent Rap runs favor precip ending in ne lower by midnight, whereas the Nam keeps some precip in ne lower MI all night long. The going forecast is steered in between, which is fine, though the Nam has not done well today (not the biggest surprise). Could perhaps still need a likely pop to start the evening in parts of ne lower and near Drummond Isl, otherwise chancy pops or less that will (slowly) fade away during the night. Leftover soupy low-level airmass will be fog- prone tonight with any breaks in the cloud cover. For Friday, we have considerable mid/high clouds streaming in, and a cu field will flare up beneath it during the day. Stratus could well be hanging on in parts of ne lower MI, though that should mix out toward midday. Some steepish mid-level lapse rates cruise by sw sections thanks to warm advection aloft (just above 7 c/km above 600mb). Would not rule out a stray shower or two, but certainly most of northern MI will be dry on Friday. Sunshine will be somewhat limited though, which will hinder temps. Would expect eastern upper to see a bit more sun than northern lower. Min temps tonight rather mild, near 50f. Max temps Friday mid/upper 60s, a few spots (including TVC) pushing 70f. && .SHORT TERM...(Friday night through Sunday) Issued at 254 PM EDT Thu May 25 2017 ...Mostly dry Saturday; increasing rain chances Sunday... High impact weather potential...Minimal, though a few thunderstorms possible on Sunday. Pattern Synopsis/Forecast...Weak upper ridge will flatten out as its axis crosses the Upper Great Lakes Friday night. A weak tilted shortwave will then ripple across northern Michigan through Saturday morning with a corresponding surface low crossing downstate. Upper flow pattern then turns SW and becomes more amplified heading into Saturday night and Sunday as a deep upper low over Central Canada wobbles southeast into the Upper Midwest. This will carry a few weak disturbances through northern Michigan. With sufficient moisture in play (PWATs of 0.8" to 1" or higher) these features will result in nuisance showers at times over the weekend. The better chances for showers look to be Friday night for mainly parts of northern Lower as the shortwave moves through, and then the second half of Sunday for all of northern MI as the deeper trough approaches with stronger forcing. Saturday will feature a partial decrease in clouds through the day as well as 850mb temperatures rising from around 8C to near 12C. This will result in a nice jump in surface temperatures with highs in the mid 70s across interior northern Lower, possibly flirting with 80 in a few spots as suggested by a few GEFS/SREF members. Cloudier skies, showers, and cooler temperatures aloft will result in highs being a few degrees cooler on Sunday. Primary Forecast Concerns...Rain chances through the weekend will be the main forecast challenge. Now showing a slightly stronger shortwave tracking a bit farther north, the 25.12Z NAM/GFS both came in wetter than their 06Z counterparts for Friday night across northern Lower. At this point, the NAM`s northern jump and QPF looks overdone, so will keep the better shower chances just brushing our far south. Can`t also rule out isolated showers across eastern Upper, but the better forcing will be found over Lower MI. Light prevailing winds will allow for the possibility of lake breezes developing Saturday afternoon that could trigger an isolated shower or two (very low probability). Otherwise it looks to be a benign weather day and the pick day of the holiday weekend. Rain chances will increase heading into Sunday, especially towards afternoon. There will also be some marginal instability (SBCAPEs perhaps approaching 1000 J/kg in spots) as a ridge of higher theta-e noses into northeast Lower. Will therefore introduce a chance of thunder in Sunday`s forecast. .LONG TERM...(Sunday night through Thursday) Issued at 254 PM EDT Thu May 25 2017 Unsettled weather expected through much of next week as deep H5 trough sits over the Great Lakes. This will also bring temperatures near, and slightly below, normal through the week. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 1042 PM EDT Thu May 25 2017 Not a whole lot of change from earlier, with more IFR/MVFR producing low clouds pinwheeling southwest across the area through early this morning. Still expect the worst conditions to occur at KAPN, with more persistent IFR cigs and occasional light rain and drizzle. Already seeing plenty of mist, especially at KAPN. This trend should continue, and will definitely still need to be on the lookout for more fog development. Cigs expected to gradually lift later today as low level drying becomes more aggressive. Light winds through the duration. && .MARINE... Issued at 254 PM EDT Thu May 25 2017 Somewhat gusty NE winds will diminish this evening as they back to the NW overnight. Wind direction will vary heading into Friday and the holiday weekend, but wind speeds will remain rather light. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...NONE. LM...NONE. LS...NONE. && $$ UPDATE...MSB NEAR TERM...JZ SHORT TERM...MEK LONG TERM...ALM AVIATION...MSB MARINE...MEK
Area Forecast Discussion
National Weather Service Brownsville TX
646 PM CDT Thu May 25 2017 .DISCUSSION...Updated for latest aviation discussion below. && .AVIATION...Tight pressure gradient across Texas and the Gulf of Mexico will keep breezy SE winds going until an hour or so after sunset, with winds expected to remain at moderate levels through the night at all of the terminals. Winds quickly pick back up to breezy levels by mid-morning, continuing into the afternoon, but do not expect Airport Weather Warning criterion of 35KT to be threatened at either BRO or HRL. Lowered CIG slightly for the overnight hours at all three terminals. Confident that MVFR ceilings will develop, though there could be brief periods of scattering out, as suggested by MOS guidance and RAP forecast soundings. Full VFR should return by early afternoon as the cloud layer mixes out. && .PREV DISCUSSION... /issued 249 PM CDT Thu May 25 2017/ SHORT TERM (Tonight through Friday Night): 500mb ridge across the central United States this afternoon will begin to move eastward tonight into Friday as a 500mb subtropical ridge develops across northeast Mexico and the Rio Grande valley. This will continue to provide subsidence across the CWA even as an onshore flow continues to increase across the lower Texas coast tonight into Friday. Very warm...breezy and humid conditions will prevail across the Rio Grande valley and northern ranchlands tonight through Fri night with no rain chances expected through the period. LONG TERM (Saturday through Thursday): Hot and dry weather will prevail Saturday with weak ridging over the southeast United States and high pressure over the Gulf. High temperatures locally will range from the lower 90s to above the century mark. Heat index values will increase to between 105 and 110 degrees Saturday afternoon. A front will overtake the dry line upstream, provoking convection over the Big Bend area of Texas. By Sunday, with a mean trough over the upper Midwest and ridging again building over the western United States, high pressure will spill southeast from the upper northwest United States, pushing into central Tex. A similarly hot day relative to Saturday will prevail Sunday, with upstream convection edging closer with the slow moving front. Convection will fire over the RGV Plains Sunday night with a few cells possibly moving into the northwest sector of the CWA. The front will approach the CWA on Monday, less emphatically than before, with winds weakening and with some uncertainty as to whether the front will have enough push to make it through. At any rate, the atmosphere will be slightly destabilized resulting in an increase in rain chances, particularly inland, where convection may fire late Monday night into Tuesday morning. Southeast flow will regain its footing on Tuesday and Wednesday, plus a destabilizing mid level low will approach from the west, with diurnal showers firing over the CWA while the lingering front is stalled or pushed back north. Only by Thursday will rain chances settle down to the more benign coastal sea breeze type, as the upstream low edges northeast. A weakness above the southwest Gulf may begin to trigger convection offshore the latter half of next week. MARINE (Tonight through Friday night): Seas were near 4 feet with south to southeast winds near 21 knots at buoy020 this afternoon. Moderate to strong south to southeast winds will prevail across the coastal waters tonight as low pressure across the southern plains and high pressure across the eastern Gulf of Mexico provides a tight pressure gradient across the western Gulf. Will go ahead and extend the SCA for the bay waters through this evening and post an SCA for the offshore for this evening through Fri morning. The pressure gradient will remain strong across the coastal waters Friday and small craft advisories will be needed for the Laguna Madre Fri morning and the SCA for the offshore waters may need to be extended possibly through Fri afternoon. Small craft advisories will be needed for the offshore waters for Fri night for strong southeast winds. Saturday through Tuesday night: A persistent pattern of high pressure will dominate the Gulf during this period. Thus, look for mainly moderate southeast winds and seas. Seas of four to six feet will be common offshore, qualifying for small craft should exercise caution headlines. && .BRO WATCHES/WARNINGS/ADVISORIES... TX...None. GM...Small Craft Advisory for winds until 9 PM CDT this evening for GMZ130-132-135. Small Craft Advisory until 7 AM CDT Friday for GMZ150-155-170- 175. && $$ This product is also available on the web at: HTTP://WEATHER.GOV/RGV 53-Schroeder/65
Area Forecast Discussion
National Weather Service Buffalo NY
1049 PM EDT Thu May 25 2017 .SYNOPSIS... An upper level low will track just to the south of the region overnight and Friday, maintaining cool, cloudy conditions with scattered light rain showers. Temperatures will moderate back to normal for the weekend, though there will remain a chance for a shower early Saturday, and then more widespread showers and perhaps a thunderstorm later Sunday and Sunday night. && .NEAR TERM /THROUGH FRIDAY/... A closed upper low will move into Southern New England overnight. Meanwhile latest surface analysis shows a broad surface low reflections loosely centered across Eastern Pennsylvania. There are spotty showers and some drizzle across Western New York, which will continue overnight. As the surface low passes, a subtle northerly flow will mix two already moist air masses with lots of low level moisture and some fog likely to develop south of Lake Ontario late this evening. Tomorrow the surface low will become better organized off the mid- Atlantic coastline, though a surface trough will linger westward behind this low. Within this trough, and under a west to northwest flow will remain chances for a few sprinkles/light rain showers through the day Friday. As the deeper moisture slides eastward tomorrow the light shower activity will end through the day. Temperatures will remain nearly steady tonight under the thick cloud cover with lows in the lower to mid 50s. With the upper level trough still overhead, highs tomorrow will only rebound back to the low to mid 60s. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/... Weak surface-based ridging will slide eastward into our region from the Central Great Lakes and Ohio Valley Friday night and Saturday. In addition, heights aloft will build over the region as shortwave ridge pushes east into the region. A wave embedded within the northern edge will slide across the region with the possibility of a few stray showers Friday night and Saturday morning with the Southern Tier having the best chance to see any measurable precipitation. The arrival of somewhat drier air behind the wave from mid day through the afternoon should help to bring some partial sunshine. Weak warm air advection and sunshine should allow afternoon highs to reach the upper 60s to lower 70s. Surface and upper ridging remains over the area for much of Saturday night. Lead wave ahead of main upper trough will drop into the Great Lakes as associated surface wave moves into the Ohio Valley. For the most part Saturday night will be dry, before the leading edge of some scattered shower activity returns to far western sections toward Sunday morning. Latest models continuing to highlight the Sunday and Sunday time frame with increasing chances for showers and embedded thunderstorms, as the deepen trough moves in from the west. Models remaining inconsistent on timing, but with the combination of falling heights and warm air advection on the eastern flank we should see showers and embedded thunderstorms fill in during the day, especially by afternoon and continuing into Sunday night. Temperatures look to remain above average with highs in the lower to mid 70s Sunday followed by lows in the mid to upper 50s Sunday night. && .LONG TERM /MONDAY THROUGH THURSDAY/... For much of next week a large upper level low will slowly meander its way across the Great Lakes and southern Canada. As a result temperatures will trend from slightly above normal values Monday (highs in the low 70s ) to slightly below normal values by mid-week (highs in the 60s). Several shortwaves embedded in the general cyclonic flow will support numerous opportunities for scattered showers across the region, with a few embedded thunderstorms also possible with the steep lapse rates aloft. && .AVIATION /03Z FRIDAY THROUGH TUESDAY/... Flight conditions are expected to deteriorate further tonight. IFR conditions are already quite prevalent south of Lake Ontario at 02Z TAF and as the weak surface low passes to the south a light northerly flow will cause upsloping and mix two already moist air masses resulting in very moist boundary layer conditions. IFR or lower conditions are expected south of Lake Ontario at BUF/IAG/ROC/JHW, with LIFR/VLIFR conditions possible in very low CIGS and fog later tonight. This trend is indicated by forecast BUFKIT soundings, and supported by HRRR and MOS guidance. Otherwise, there will be some light showers or drizzle lingering overnight, but this will have little impact on flight conditions. Friday, with a still light westerly flow flight conditions will slowly improve back to MVFR with daytime mixing and deeper moisture exits to the east. This is likely to be a slow process, with IFR conditions likely to linger through most (if not all) of the morning hours south of Lake Ontario. Outlook... Friday night...MVFR/VFR with isolated showers. Saturday...Mainly VFR. Chc of showers early to the west. Sunday...Mainly MVFR with showers likely. Monday and Tuesday...MVFR/VFR with a chance of showers. && .MARINE... An easterly wind will continue across Lake Ontario this evening with small craft advisory worthy waves and winds on the far western shoreline. Otherwise an upper level low will track across Lake Erie and to the south of Lake Ontario overnight and tomorrow. Winds will relax under this feature and this will allow for the SCA to end overnight. && .TIDES/COASTAL FLOODING... Low pressure will track from Pennsylvania to Southern New England. Winds have diminished this evening, but there are waves up to 5 ft across western portions of Lake Ontario so we kept the lakeshore flood warning up for now with this set to expire at 2 am. && .CLIMATE... Buffalo has exceeded the daily precipitation record of 1.21 inches established in 1874. Rochester is close to a recorded rainfall, while the rain continues across Watertown. Daily record rainfall for Rochester is 1.74 inches set back in 1943 and Watertown`s record for today is 1.13 inches set back in 1979. With rain continuing east of Lake Ontario, and possible showers across Buffalo and Rochester final daily totals be known after the climatic day (1 AM EDT to 1 AM EDT) ends. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...Lakeshore Flood Warning until 2 AM EDT Friday for NYZ001>003. MARINE...Small Craft Advisory until 2 AM EDT Friday for LOZ042. && $$ SYNOPSIS...APFFEL/THOMAS NEAR TERM...APFFEL/THOMAS SHORT TERM...TMA LONG TERM...CHURCH AVIATION...APFFEL/THOMAS MARINE...APFFEL/THOMAS TIDES/COASTAL FLOODING...HITCHCOCK/WOOD/APFFEL/THOMAS CLIMATE...THOMAS
Area Forecast Discussion
National Weather Service Dodge City KS
623 PM CDT Thu May 25 2017 ...Updated Aviation Discussion... .SHORT TERM...(This evening through Friday) Issued at 259 PM CDT Thu May 25 2017 Higher surface dew points will be gradually streaming north from the southern Plains today through tomorrow. Both days, high plains convection will be forming over central Colorado, and feeding into the instability/CAPE axis into western Kansas late in the day. The latest HRRR and 4 km NestedNAM drive clusters of convection through the I-70 corridor from around 2 to 4 UTC this evening, tying into the northern periphery of the low level moisture advection wind field convergence along the trailing edge of a weak northern Plains cold front. These storms are already forming across northeast Colorado. Stratus clouds may develop across central Kansas behind this boundary toward the late overnight hours and the SREF probabilities indicate, however the boundary will wash out with rapid warming and a return to light easterly surface winds. Lee side toughing develops again on Friday, with much higher low level moisture to work with farther west. The NAM focuses another area of convection near the best surface convergence over north CO and driving a meso low across nw KS late Friday evening/night. .LONG TERM...(Friday night through Thursday) Issued at 259 PM CDT Thu May 25 2017 High surface pressure will be anchored over the northern Rockies through the southern Plains. Showers and isolated thunderstorms may linger behind the boundary into Saturday morning, however organized convection opportunity appear to shut down late Saturday into Sunday. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 621 PM CDT Thu May 25 2017 A cold front will cross southwest Kansas overnight. As this frontal boundary passes the winds will shift to the north northeast at 15 to 20 knots. Prior to the frontal passage tonight some widely scattered thunderstorms will be possible. A few of these thunderstorms will be near the GCK airport for the next few hours and then weaken as they approach the DDC airport towards sunset. Around the HYS airport there will be a chance for VCTS after sunset as scattered thunderstorms cross north central Kansas between 02z and 06z. Model soundings indicating VFR conditions for most of the night. The potential exists for brief period of MVFR conditions from 10z Friday to 15z Friday at DDC and HYS behind the surface cold front. && .PRELIMINARY POINT TEMPS/POPS... DDC 57 80 59 76 / 20 10 20 20 GCK 55 80 57 75 / 20 20 20 20 EHA 55 81 55 77 / 10 20 10 20 LBL 56 82 57 79 / 10 20 10 20 HYS 57 78 58 73 / 40 10 30 30 P28 60 84 63 82 / 10 0 10 20 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Russell LONG TERM...Russell AVIATION...Burgert
Area Forecast Discussion
National Weather Service Grand Forks ND
1001 PM CDT Thu May 25 2017 .UPDATE... Issued at 958 PM CDT Thu May 25 2017 Narrow band of showers on leading edge of short wave and along surface boundary propagating ne. Handled best by the HRRR these should gradually diminish in coverage next several hours. adjusted pops accordingly with no other changes. UPDATE Issued at 638 PM CDT Thu May 25 2017 Showers across the far se-e not very impressive but will continue with low pops into the evening. Otherwise some minor cloud cover adjustments with the remainder of the forecast ok. && .SHORT TERM...(This evening through Friday) Issued at 312 PM CDT Thu May 25 2017 Main challenge into tonight will be decreasing winds and any lingering showers. Winds in the Red River Valley have peaked and will continue a slow decrease now into the early evening. Winds have already decreased in the Devils Lake region, but they may increase a bit again as the westerly winds and clearing come in. There are still a few showers, mainly in the northeast FA, moving northeast. High resolution models show some additional shower development over northeast ND into northwest MN by early evening, continuing into late evening. Confidence low in this additional shower development, but if it does form, pcpn amounts would be minimal. Clouds should decrease from west to east tonight, with a little more sun around Friday morning as well. Clouds will likely increase again during the afternoon, but not quite as extensive as today. Areas with more sun will be a little warmer, which should be areas along/south of highway 200. There may be a few showers in the far east on Friday as well, but again pretty minimal if at all. .LONG TERM...(Friday night through Thursday) Issued at 312 PM CDT Thu May 25 2017 Pronounced upper low swirling from Saskatchewan to Manitoba over the weekend will send spokes of upper instability into the Northern Plains over the weekend, but the forecast area will be under west to northwest flow resulting in mainly dry weather with near seasonable temperatures. An exception could come Sat aftn into early evening as a shortwave combines with modest CAPE and marginal LI/Showalter indices to create shower chances with possibilities for isolated thunder. The same situation presents itself for later Sun as the next wave heads down from the NW enhancing chances for convection. The upper low over Manitoba will gradually migrate to the east through the middle and end of next week, winding up in central Ontario. The scenario will be that of a longwave ridge hung up over the northern Rockies with the broad trough over the Ohio Valley and Midwest. Little movement is expected with our area remaining in northwest flow. Surface systems won`t be very distinct, but some wraparound type pcpn combined with 850 mb temps barely above 0 C will make for a cool Memorial day with highs only within a few degrees of 60. Improvement should come during Tue with a return to dry weather and more seasonal readings Wed and Thu. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 638 PM CDT Thu May 25 2017 VFR conditions through the period with main challenge being timing of wshft however winds will not be strong. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...Voelker SHORT TERM...Godon LONG TERM...WJB AVIATION...Voelker
Area Forecast Discussion
National Weather Service Gray ME
1041 PM EDT Thu May 25 2017 .SYNOPSIS... A broad area of low pressure from the Ohio Valley through the mid Atlantic coast will slowly lift northeast tonight...reaching Cape Cod by Friday morning. Low pressure will continue northeast into the maritimes through Friday night. Weak high pressure will build over the area on Saturday and will shift offshore on Sunday. Weak low pressure over the eastern Great Lakes will lift north into western Quebec Sunday night and will drive a cold front toward the region on Monday. The front will slowly cross the area Late Monday night and Tuesday. && .NEAR TERM /TONIGHT/... 1045PM UPDATE... Initial batch of rain has developed and begun pushing onshore over much of Maine this evening, while another more substantial area of rain is finally taking shape to the south of Rhode Island. HRRR model is handling both areas of rain quite well, and based the forecast update largely on this. Precipitation from the heavier band to the south should be arriving in southern New Hampshire around midnight. Thunderstorms are currently noted with this activity as it is forming. As this wraps around the low, expect the thunderstorm activity to decrease a bit, but there could still be some rumbles of thunder across the southern part of our area overnight as this low winds up. Have increased precipitation amounts as well, as even this earlier area of rain forming along the coast of Maine has produced some decent rainfall rates. Area moving in from the south could produce rates up to about an inch per hour, though the heaviest rain should only last an hour or two before becoming light and drizzly. 945PM UPDATE... Getting a few reports of high, gusty winds. Have increased wind forecast for the overnight hours, especially through 06Z where best wind fields will be in place from the northeast. Otherwise, have updated the forecast based on current conditions and latest set of mesoscale models. Rain continues to spread north and east, however it remains fairly light and fragmented in most areas. Heaviest precipitation remains over Upstate New York well to our west. However, satellite imagery continues to show a large plume of moisture forming off the Mid Atlantic coastline and moving quickly to the north. Mesoscale models have this heavier precipitation arriving from south to north within the 06Z and 12Z time frame. Have made minor adjustments to pops and temperatures for the next 6 hours. Areas of light rain will continue with downsloping over the northern Connecticut River Valley. ORIGINAL DISCUSSION... Higher pressure and easterly winds have kept much rain from intruding into northern New England by retarding the advancement of precipitation into Maine and northern and central NH until the last couple of hours. The flow has intensified along the coast as the pressure gradient increases/low pressure nears. Temperatures have been kept down in this marine airmass while northern sections were able to break out into the 60s. CAM models have been correct in showing a weakness this afternoon in precipitation fields over NH and especially Maine as energy diverges both towards northern NY State as well as offshore. We`ll see a break in most shower activity more or less this afternoon and evening...however there will be widely scattered showers still around...mainly over the mountains. Around midnight a stronger short wave associated with this system will pivot into the area and precipitation will increase both in intensity and areal coverage. This is when we will see the bulk of the 1-2 inches with this event. We`ll see some heavy downpours for the overnight period into Friday morning. Winds are picking up as mixing deepens today and expect ESE winds to gust to 25 kt through the night. Continued with drizzle tonight mainly in between the two systems as the onshore flow intensifies. Lows will be in the upper 40s to around 50. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/... After the heavier rain expected during the morning hours...precipitation tapers off to showers by Friday afternoon. Again the heavier rain will be along the coast with some enhancement over terrain. The long duration of this event should preclude any flooding issues but poor drainage areas may see some brief issues in heavier rainfall that occurs through tomorrow. Expect temperatures to warm only about 5-10 degrees from overnight lows tonight to highs Friday. Tomorrow night clouds will begin to decrease across the region. The upper low will be engulfed in another circulation south of Greenland while the surface cyclone fills. Overnight lows Friday night will drop farther in a drier airmass with lows in the 40s most locations and perhaps up to 50 degrees in warm spots. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Mean long wave trof position will remain over the Great Lakes, this will mean a general cool wet pattern can be expect for the outlook period with a few dry periods between systems. Starting with Saturday, the system that exits into the maritimes allows weak high pres over the area and a drier north to northwest flow to develop for Saturday into Sunday with cool temps. By late Sunday into Monday, the next short wave that rotates around the base of the Great Lakes trof then moves northeast bringing another period of wet weather with a developing onshore flow that keeps temps cool. With the mean upper trof remaining over the Great Lakes through mid week a continue unstable southwest flow with embedded short waves with keep unsettled conditions through Wednesday. It appears we may finally get rid of the onshore flow by midweek so temps may actually get back to near normal high temps reaching into the 70s. && .AVIATION /03Z FRIDAY THROUGH TUESDAY/... Short Term...IFR/LIFR ceilings developing today and persisting through tomorrow. ESE winds will gust to 25 kts most terminals through tomorrow. Early on LLWS will affect HIE and LEB tonight. Drizzle and fog will affect most TAF sites outside of HIE and LEB tonight before the moderate to heavy rain arrives. Long Term...Winds and seas generally light. No flags. && .MARINE... Short Term...Continuing SCAs through Friday afternoon. At that point we may need a SCA just for high seas for the outer waters. Long Term...Conditions become VFR Sat into Sun before returning to MVFR conditions for Sun night and Monday and possibly through midweek in scattered showers. && .TIDES/COASTAL FLOODING... Highest astronomical tides of the year on tap for tonight and Friday night. A Coastal Flood Advisory remains in place the Midcoast region of Maine. The astronomical tide in Portland is 11.8 feet near midnight tonight. Expect around a foot of storm surge overnight. Flood stage in Portland is 12 feet and a storm tide will likely be near 13. Areas of flooding are expected with pockets of moderate flooding. Have therefore upgraded the Coastal Flood Advisories from Portland south to warnings. We may need a Coastal Flood Statement for the tide tomorrow night despite the absence of an onshore wind as astronomical tides will be at the flood stage of 12.0 feet in Portland. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...Coastal Flood Advisory until 1 AM EDT Friday for MEZ025>028. Coastal Flood Warning until 1 AM EDT Friday for MEZ023-024. NH...Coastal Flood Warning until 1 AM EDT Friday for NHZ014. MARINE...Small Craft Advisory until 8 PM EDT Friday for ANZ150>154. && $$ NEAR TERM UPDATE...Kimble SHORT TERM...Hanes LONG TERM...Marine
National Weather Service Jackson KY
1027 PM EDT Thu May 25 2017 .UPDATE... Issued at 1027 PM EDT THU MAY 25 2017 Went ahead and removed precipitation from the forecast for the rest of the night. The last showers should be out of the area by the top of the hour, and with no new development upstream, it seemed reasonable to go ahead and axe precip for the rest of tonight. The rest of the forecast was in good shape. UPDATE Issued at 748 PM EDT THU MAY 25 2017 Updated the forecast to reflect precipitation exiting the much quicker than the inherited forecast had been suggesting. The latest NAM12 and HRRR have eastern Kentucky precipitation free by 5 or 6Z tonight. Based on current decrease in areal coverage of precipitation seen in the latest radar imagery, decided it was reasonable to get precip out of here earlier than previously thought. The rest of the forecast should be in good shape as is. && .SHORT TERM...(This evening through Friday night) Issued at 408 PM EDT THU MAY 25 2017 An upper level low pressure system continues to shift NE of Kentucky this afternoon, pulling with it the surface low which is currently located over north-central Ohio. Moisture from this system has impacted much of eastern KY today with widespread stratiform rain. However, as the system continues to shift NE of the region, this rain will continue to move east and taper off throughout the afternoon/evening. With no instability to work with, continued with no thunder in the forecast during this time. Upper level ridging and surface high pressure will work in overnight tonight, but llvl moisture may linger a bit in the form of low clouds, eventually breaking up by daybreak Friday in many locations. A warm front moving in to our north will likely keep cloud cover in place across the NE CWA. According to the latest soundings, this llvl cloud cover should be enough to prevent fog in most locations, though can`t rule out some isolated valley occurrences. During the day Friday, another surface low pressure system will be located over the Southern Plains tracking NE into the Mid Mississippi Valley. This will send a warm front eastward into Kentucky during the day Friday into Friday night, with the return of southerly winds pulling moisture off of the Gulf of Mexico. Temperatures will shoot up to near 80 by Friday afternoon, compared to our 60 degrees today. Precipitation will also start moving in along the Ohio River Friday night, before spreading into our region during the day Friday. This could bring some pops into our northern CWA to round out the short term portion of the forecast. However, after looking at the latest NAM12 forecast soundings, all moisture should be confined to a fairly shallow layer in the llvls, with a very strong inversion located just above followed by dry air aloft. In such a setting, there is nothing to support convection, so kept with only rain mention in the grids during the overnight. Southerly flow will also help keep overnight temps from bottoming out Friday night/Saturday morning, only falling to the low to mid 60s. .LONG TERM...(Saturday through Thursday) Issued at 447 PM EDT THU MAY 25 2017 The long wave pattern reveals amplifying flow once again into next week. An upper level low will deepen across south central Canada, with troughing taking shape across the Mississippi Valley into early next week. A baroclinic zone will be laid out initially along the Ohio Valley, with several short wave troughs traversing the flow. This will bring continued storminess to eastern Kentucky, with the possibility of severe weather as well as flash flooding, given the already wet conditions in place. Will continue to highlight these threats in the HWO. Cyclonic flow will linger into next week across the Great Lakes and Ohio Valley regions, as the Canadian upper level low gradually spirals its way east. The baroclinic zone will drop south, yielding some return of drier weather; however, a few POPs may linger during peak heating in places between Tuesday and Thursday, with the surface boundary still in the vicinity of the area. For temperatures, slightly above normal readings will build back into the region for this weekend as highs return to around the 80 degree mark. Humidity levels will also be on the rise. Once the front exits to the south on Monday, generally near to slightly below normal readings can be expected through the rest of the period, with lower humidity levels. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) ISSUED AT 748 PM EDT THU MAY 25 2017 As an area of low pressure rotates of to our east this evening, expect any lingering rain showers to come to an end at JKL, SYM, and SJS between 0 and 5Z tonight. CIGS and VIS will remain borderline IFR to MVFR up until this point. After the rain clears out, CIGS will increase a bit, though may still remain MVFR throughout the night. The latest forecast soundings are not supporting much in the way of fog with the thick clouds in place. Skies will slowly start to break up into the day tomorrow, with generally SCT MVFR to low end VFR cigs. Winds will lessen to generally less than 10 knots overnight, and then to less than 7 knots by during the day Friday. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AR SHORT TERM...JMW LONG TERM...GEOGERIAN AVIATION...AR
Area Forecast Discussion
National Weather Service Elko NV
355 PM PDT Thu May 25 2017 .SYNOPSIS...Friday will be cooler across the reigon with a threat for scattered showers and isolated thunderstorms for mainly northeast Nevada. High pressure will rapidly build into the region for the weekend with temperatures warming into the 70s. By the middle and early portion of next week, highs will be in the 80s. && .SHORT TERM...Today through Saturday. Currently the radar is showing a few isolated showers or sprinkles across eastern White Pine, but little if anything is probably reaching the ground. More likely heavy virga, which could create some gusty winds. The HRRR model has this activity rapidly moving eastward and weakening through the rest of the aftn. By later tonight through tomorrow, a weak closed low will quickly move from NW to SE near the NE corner of NV. This will start to bring some valley rain showers and mtn snow showers to far northern NV. The HRRR has been very consistent on this solution. With the lowering snow levels, the higher peaks of the Bull Run and Jarbidge mtns could see 1-3 inches of snow, but no issues expected below 7500-8000ft. As the low slides by the region, another shortwave will pinwheel around through Elko County. This will bring enough moisture and instability (300-600 j/kg CAPE) to produce isolated thunderstorms and scattered showers. Some of the storms could have gusty winds and small hail, but lack of better forcing, shear, and instability will preclude coverage and intensity concerns. Snow levels will rise to the highest peaks, despite the cooler air aloft. By Saturday, heights rapidly begin to rise with a noticeable warming trend. This will likely begin a long period of warm and dry conditions. .LONG TERM...Saturday night through next Thursday. There is potentially a lengthy dry period ahead. Model agreement is pretty good through Monday, then there are some issues arising as high pressure breaks down. Saturday night through Monday. High pressure will expand dramatically over the Great Basin. Model QPF is showing up as minimal to nonexistent. Will keep the forecast dry with some cumulus buildups possible under the massive ridge pattern. There could be a thunderstorm or two pop up however the tendency would by toward the dry variety with PWs generally in the low to mid 30s. High temperatures will range from the mid 70s to the mid 80s. Low temperatures will be in the 40s. Monday night through Thursday. There is some model discrepancy in this time-frame. A low pressure area will be trying to nudge the ridge out of position and it is difficult to say how much resistance the ridge will display. The biggest difference is the upper low generated by the ECMWF model off the Pacific coast progged to cut through southern California and the northern Baja region, scooping up some moisture along the way that could make its way into eastern Nevada. The GFS has no such upper low but rather goes with a gentle trough intrusion from the northwest on Monday and Tuesday, with a possible frontal passage across northern Nevada on Wednesday and/or Thursday as it skips across the north. Too much discrepancy to lean one way or the other thus will have some light pops shaded in but will not generate any weather at this juncture. && .AVIATION...Wind gusts around 25 kts will continue through early this evening at KELY and KTPH. There is a still a small risk for thunderstorms to affect KELY this afternoon and evening, and KEKO Friday afternoon and evening. However VFR conditions should still hold at all four stations...KWMC KEKO KELY and KTPH. && .HYDROLOGY...Cooler temperatures will serve to slow snowmelt over the next few days, however temperatures have not been dropping to freezing at night. Thus snowmelt continues to add flow to the streams around the clock. Also, much warmer temperatures will return next week. All creeks that flow out of mountainous areas will see a significant rise by next week. The lower Humboldt River from Comus downstream through Winnemucca to the Humboldt/Pershing County border will experience minor to moderate flooding through the weekend. A Flood Warning is in effect. The Jarbidge River is expected to experience fluctuating water levels around minor flood stage over the next several days. A Flood Warning is in effect. Lamoille Creek is expected to reach Minor Flood Stage as early as this evening, and will likely peak each evening thereafter into flood stage. A Flood Warning is in effect. The Humboldt River at Battle Mountain has dropped below flood stage. The Flood Warning has been cancelled. The Bruneau River is rising and minor flooding may be possible by this weekend. Wildhorse Reservoir is still above the spillway. There is no threat for flooding at this time downstream along the Owyhee River. && .LKN WATCHES/WARNINGS/ADVISORIES...None. && $$ 94/92/92
Area Forecast Discussion
National Weather Service Miami FL
853 PM EDT Thu May 25 2017 .UPDATE... Went ahead and removed thunderstorms from the forecast for the overnight hours. With the lack of convective activity, other than a lone shower over Palm beach County, hard to keep them in for the remainder of the night. Also, made adjustment to PoPs to account for latest HRRR run and current activity. Slowly brought slight chance PoPs down the east half, mainly along the coast, as the front continues to make its way south. The latest HRRR run shows mostly isolated shower activity, if any at all. It keep most of the showers offshore, but kept some showers in the forecast to account for error in the model run. Also, given the lower wind speed over the Gulf,and that the latest marine model lowers the rip current risk for the gulf overnight, dropped the moderate risk for the Gulf coast beaches. no other significant changes made to the forecast at this time. && .PREV DISCUSSION... /issued 757 PM EDT Thu May 25 2017/ UPDATE... The frontal boundary is progressively moving southeastward over South Florida this evening. Coverage of rain has decreased over the past few hours. For this update, lowered PoPs over land areas of SE Florida for tonight through 09Z based on latest radar trends and the latest HRRR forecast. HRRR still shows scattered showers forming along the boundary over the extreme southeast portion of the Peninsula and offshore, so maintained 30-40 percent rain chances Friday beginning at 09Z. Southeast portions of the peninsula will see scattered showers and isolated thunderstorms Friday morning. The highest rain chances will migrate to southern interior areas early Friday afternoon due to daytime heating. PREV DISCUSSION... /issued 734 PM EDT Thu May 25 2017/ AVIATION... A weak cold front is currently moving across South Florida this evening, and will continue to slowly move through during the overnight hours. The front may stall along the far southern edge of the peninsula. The forecast is for VFR conditions through the night, with showers all but over across the area. A few isolated are persisting into the evening hours near PBI. Otherwise, the wind is forecast to be light and variable overnight,although it may have a west northwest tendency. Tomorrow, the wind will pickup out of the northwest, before yielding to a sea breeze for all TAF sites by the afternoon hours. PREV DISCUSSION... /issued 334 PM EDT Thu May 25 2017/ DISCUSSION... A broken line of thunderstorms pushing across South Florida is located just ahead of a cold front this afternoon. The front is forecast to slow down and become stationary over the extreme southern part of the peninsula tonight into early Friday. Showers/storms should decrease in coverage this evening and will mainly be confined to the far southern part of South Florida and marine areas. For Friday, northern portions of South Florida will see drier conditions with lower relative humidity, but southern areas will still see a risk for a few showers and thunderstorms especially during the afternoon. The front will wash out by Saturday as high pressure builds into the region for the weekend. Above normal temperatures are expected this weekend, and heat indices will likely be near 100 degrees by Saturday for portions of South Florida. An afternoon thunderstorm or two cannot be ruled out over interior South Florida this weekend as converging sea breezes could spark some isolated activity. However, for the most part, Saturday through Monday should feature hot weather, relatively light winds and only slight rain chances. Rain chances should then increase somewhat by the middle of next week as the high pressure begins to shift eastward and weaken. This will allow for a flow of somewhat moister air over the region. MARINE... Winds and seas will be decreasing this evening, becoming light overnight. Relatively benign marine conditions are then expected to persist Friday through the weekend and into early next week. Sea breezes will develop each day over the holiday weekend, so winds could be as high as 10 kts with gusts to 15 kts for a few hours in the late morning to early afternoon right near the coast. Another exception to the benign conditions would be near any thunderstorms, where locally enhanced winds and seas could occur. && .PRELIMINARY POINT TEMPS/POPS... West Palm Beach 72 88 74 92 / 20 10 10 10 Fort Lauderdale 76 90 79 91 / 20 40 30 10 Miami 76 90 78 92 / 20 40 30 10 Naples 73 88 74 90 / 10 10 0 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. GM...None. && UPDATE...13 DISCUSSION...98/ABH MARINE...98/ABH AVIATION...13
Area Forecast Discussion
National Weather Service Marquette MI
740 PM EDT Thu May 25 2017 .SHORT TERM...(This evening through Friday) Issued at 414 PM EDT THU MAY 25 2017 WV imagery and RAP analysis indicated mid/upper level trough over the wrn CONUS with a downstream ridge from the cntrl plains through the upper MS valley into nw Ontario. At the surface, riding also prevailed from the lower MS valley through WI to wrn Lake Superior. Vis loop showed mostly sunny skies over most of nrn Upper Michigan with sct/bkn cu over the south. Moisture and a weakening deformation zone with a mid level low from OH to Lake Huron supported clouds and light rain over far eastern Upper Michigan. Tonight, the slowly progressive pattern will allow the sfc ridge to build into cntrl and ern Upper Michigan. A period of partly to mostly clear skies this evening will allow temps to drop into the mid and upper 40s. There should also be enough mosture, dewpoints in the mid 40s, along with the period of favorable radiational cooling for some fog formation. 850-700mb WAA with 295k-305k isentropic lift may also support light rain over nw WI that could spread into the wrn cwa late. However, since the lift weakens as it moves eastward only slight chance pops were included. Friday, as the sfc trough moves to the east and a weak shortwave trough lifts toward wrn Lake Superior, lower end pcpn chances across the west half will increase, mainly during the late afternoon. Even with temps climbing to around 70 inland, instability to support tsra remains west of the cwa. .LONG TERM...(Friday night through Thursday) Issued at 402 PM EDT THU MAY 25 2017 An active pattern is expected through the first half of the upcoming work week; however, impacts are expected to be fairly low through the extended. Friday night: A weak trough/cold front is expected to slide across the U.P. bringing a chance of rain showers to the area. Rainfall is expected to be fairly light as the system is fairly fast moving and overall moisture is not overly impressive. In fact, models are only painting out about a tenth of an inch of QPF across the area. Saturday into Saturday evening: At this point, drier air is progged to slide across the area during this time period giving a break in the precipitation with temperatures near to slightly above normal. In fact, most locations will likely see sunshine through much of the day with high temperatures warming into the upper 60s to near 70. Clouds will begin to increase from the west Saturday evening as the next broad trough of low pressure approaches the area. Sunday through the rest of the extended: Broad low pressure will slide over the Upper Great Lakes region through this time period, allowing for mostly cloudy skies with intermittent chances for rain showers. This will also act to push temperature back down below normal through much of this time period due in large part to the increased cloud cover along with showery weather. Toward the end of this time period there may be some improvement as the low begins to shift slowly to the east. This may lead to some drier weather and more sunshine by late Wednesday afternoon into Thursday. At this point, will stick with a consensus of the models for the extended due to difficulties in timing out shortwave energy sliding in around the broad troughing. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 739 PM EDT THU MAY 25 2017 VFR conditions will likely prevail at KIWD/KCMX thru this fcst period. VFR conditions will also prevail at KSAW with the exception of late tonight/early Fri morning when radiation fog may develop. VIS will fall to MVFR, perhaps lower. Winds at all terminals will be light thru the period. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 414 PM EDT THU MAY 25 2017 Expect winds under 20 kts through early next week as a relatively flat pres gradient dominates the Upper Lakes. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JLB LONG TERM...KEC AVIATION...Rolfson MARINE...JLB
Area Forecast Discussion
National Weather Service New York NY
1100 PM EDT Thu May 25 2017 .SYNOPSIS... Low pressure tracks through the Tri-State Region tonight and off the New England coast Friday into Friday night. High pressure builds down from southeastern Canada for the weekend. This high then retreats to the northeast early next week as weak low pressure tracks to the south. A cold front approaches from the west on Tuesday, then crosses the area Tuesday night. This front then stalls out nearby as high pressure builds in from the southwest, producing potentially unsettled weather for the middle of next week. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... Updated probabilities and weather across the far eastern zones for showers and scattered thunderstorms with area moving north northeast over the ocean waters. HRRR indicating area will remain next couple of hours, so have categorical and likely probabilities. Middle level dry air continue moving over the region into this evening as impressive upper level low begins tracking from the Ohio Valley into the Middle Atlantic region. A vigorous vorticity max will round the base of the upper trough and approach the northeast as the trough goes negatively tilted tonight. Light rain remains across southern Connecticut with patchy drizzle into northeastern New Jersey. Patchy to areas of fog with visibilities around 1 mile, and up to 3 miles, were across the region. No significant rain is expected however as lift is weak and saturation is confined to the lowest 5 kft. Moisture and lift increase after 03z from south to north as the upper low and energy approach. Significant DPVA and steepening lapse rates will support showers and scattered thunderstorms. The CAPE is elevated as the low levels are inverted. The best instability appears to lie along and East of the Hudson River. Due to the anomalous nature of the upper low and strength of the energy, feel thunder is possible anywhere across the area overnight. High resolution mesoscale models, such as the HRRR, NAM-3km, and NCAR and SPC SSEO ensemble all support this reasoning. The normalized probability of greater than 40 dBZ on the SPC SSEO is over 90 percent across Long Island and southeast Connecticut 06z-12z with slightly lower percentages further west. No severe weather is forecast. Surface low pressure will move along or near the Long Island coast overnight so winds will not be as strong as earlier today. The warm front may even briefly move across portions of eastern Long Island before the low lifts to the north and east. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/... Upper low and surface low become vertically stacked as they move off the New England coast on Friday. Wrap around showers and possible thunder linger for a few hours around day break across eastern Connecticut and the Forks of Long Island. Otherwise, clouds will be slow to clear as moisture lingers below 10 kft. NW downsloping flow should help to create some breaks in the clouds, especially across the western half of the area. These breaks will help boost temperatures into the 70s, with cooler readings in the middle to upper 60s further east where clouds linger longest. Model soundings indicate some instability between about 5 and 10 kft, so clouds may fill back in with any breaks. There is also the possibility of a few iso-sct showers. No thunder is forecast since the instability does not look to get much above -5C with heights building aloft behind the upper low. Weak ridging passes Friday night as high pressure moves into the region from the west. Lingering moisture will keep skies partly to mostly cloudy with lows near normal values. && .LONG TERM /SATURDAY THROUGH THURSDAY/... The region is in between two shortwaves passing to the north and south Saturday and Saturday night, so with most significant forcing outside of the area, have at most slight chance pops in this time frame, with temperatures near to slightly above normal. Onshore flow will dominate from Sunday through Monday. The result will be mainly gray sky conditions with spotty light rain or drizzle mainly over higher elevations mainly to the N/W of NYC from Sunday into Sunday night as a northern stream shortwave ridge crosses the area. A 700-500 hPa shortwave approaches late Sunday night and crosses the area on Monday, making for a more widespread rain over the region then. With the onshore flow/damming high, have undercut guidance by mixing in NAM and ECMWF 2-meter temperatures. Highs will run 5-10 degrees below normal Sunday and Monday and lows a few degrees above normal Sunday night (due to reduced diurnal range). A broad closed low slow tracks from Ontario into western Quebec from Monday night through Thursday, with shortwaves rotating around the base of the low from time to time. the timing of these shortwaves is somewhat difficult this far out, but for now it appears that most energy will be focused mainly to the N of the region. As a result, there is a chance of isolated to scattered showers - mainly over northern portions of the Tri-state. Also, cannot rule out an isolated rumble of thunder Tuesday/Tuesday night with the passage of a surface cold front. Temperatures Tuesday-Thursday should run near to slightly above normal. && .AVIATION /03Z FRIDAY THROUGH TUESDAY/... A warm front lies just south of the terminals this evening. A weak low center then passes through during the late night hours. IFR/LIFR conds improving to MVFR at times with shra/tstms. TSTM chances drop off after around 06-08z with a return to prevailing IFR/LIFR for the rest of the night. East to NE winds around 10 kts for most terminals this evening, turning variable in direction for a couple of hours within roughly 04-08z for most terminals before a NW flow on the backside of the low gets established. Improving back to VFR by Friday afternoon. W-NW gusts 20-25 KT. Winds generally south of 310 magnetic. SHRA possible. .OUTLOOK FOR 00Z SATURDAY THROUGH TUESDAY... .Friday night...VFR. .Saturday...VFR. .Saturday Night-Monday...MVFR/IFR possible in showers. E/SE winds. .Tuesday...Improving to VFR. S/SE winds. && .MARINE... Updated weather and probabilities for showers and scattered thunderstorms early this evening across the far eastern ocean waters and into the eastern Long Island Sound. With nearshore wind gusts, and across the waters, below 25 KT the small craft advisory for the bays and New York Harbor and Long Island Sound was allowed to expire. Easterly winds will gradually weaken into this evening as the pressure gradient relaxes. Seas on the ocean will remain at small craft levels through Friday and the small craft was converted to a hazardous seas small craft. These seas will gradually subside Friday night with sub-SCA conditions elsewhere. A light pressure gradient over the region Saturday-Tuesday should limit winds to 10 kt or less. Given the absence of any significant swell, in addition, conditions should be below small craft advisory conditions over the waters around Long Island Saturday-Tuesday. && .HYDROLOGY... An additional 0.50 to 1.0 inches of rain is forecast through Friday morning. The highest amounts will likely occur across eastern Connecticut and eastern Long Island. Locally higher amounts are possible where thunderstorms occur overnight. Minor urban and poor drainage flooding is possible. It should then be mainly dry Friday night-Sunday. Another round of rain is possible from Sunday night into late Monday. At this time, it is to soon to specify, what, if any, hydrologic impact will be experienced from this system. && .TIDES/COASTAL FLOODING... A Coastal Flood Warning continues for moderate flooding potential for the south shore back bay locations of Nassau County for tonight, and advisories are in place for minor flooding potential for areas adjacent to western Long Island Sound, NY Harbor, and the south shore back bays of the western Long Island. Minor flood thresholds could briefly be touched along the eastern bays of LI and SE CT. How quickly easterly winds begin to weaken this evening will be key to the potential for seeing widespread versus localized moderate coastal flooding along the southern bays of Western LI. Less than 1/2 ft of surge is needed in many places to reach minor flood thresholds. The threat for minor coastal flooding is likely to continue during the nighttime high tides for the southern bays of Western LI/NYC through the Memorial Day Weekend. While along western Long Island Sound, lower NY Harbor, and eastern Great South Bay...minor coastal flooding is possible at those times. Beach erosion is expected with the prolonged easterly sweep...but the potential for dune erosion looks to be low and localized. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...Coastal Flood Advisory until 1 AM EDT Friday for CTZ009-010. NY...Coastal Flood Advisory until 1 AM EDT Friday for NYZ071>073- 078-176-177. Coastal Flood Advisory until midnight EDT tonight for NYZ080. NJ...None. MARINE...Small Craft Advisory for hazardous seas until 6 PM EDT Friday for ANZ350-353-355. && $$ AVIATION...JC
Area Forecast Discussion
National Weather Service Pueblo CO
820 PM MDT Thu May 25 2017 .UPDATE... Issued at 810 PM MDT Thu May 25 2017 Increased pops a little bit, into the scattered category, 04Z- 08Z, centered around 06Z (midnight). Several high res model runs from the HRRR this evening have been ramping up convection during that time around the Pikes Peak Region. Some have it centered more over Pueblo County. Others have it farther north across Teller/El Paso Counties. Taking a look at the experimental GOES-16 imagery data this evening, there is clearly an area of lift to our west coming this way. Couple this with the surface boundary that has pushed through the region, visible in radar pushing south into Las Animas County at this hour, and it seems plausible that we could generate some nocturnal convection. Confidence is not real high but high enough to raise pops into the scattered category. && .SHORT TERM...(This evening through Friday) Issued at 339 PM MDT Thu May 25 2017 ...Severe weather threat ramping up into Friday... Strong southwest flow aloft today has lead to gusty winds and low humidities across all of southern CO this afternoon. If fuels weren`t moist/green from recent rains, this would have been a critical fire weather day for all areas west of the dry line. Meanwhile the cold front across northeast CO combined with upper trof moving across the northern Rockies has sparked a round of thunderstorms just north of the forecast area. Latest HRRR drops the front south of the Palmer Divide by 23z and through most of southeast CO by 03z. Some low level moistening behind the front will allow for a window of one or two strong to severe thunderstorms across northern portions of the southeast plains through this evening, particularly northern El Paso and Kiowa counties. Activity should diminish overnight. Trailing energy dropping southward out of Canada carves out an upper low across ID which will move slowly eastward on Friday. More shortwave energy will eject eastward across CO interacting with the frontal boundary and moisture hung up in eastern CO during the afternoon. Main challenge will be forecasting how far east low level moisture will mix out during the afternoon. Have leaned towards the NAM12 solution which maintains a more westward position to the frontal boundary and puts best risk for severe thunderstorms east of a line from roughly Falcon to La Junta to Kim. Capes will be running 1000-1800 J/kg east of this axis with deep layer shears around 40 kts. Main threat will be hail and damaging winds with supercell thunderstorms, however would think an isolated tornado threat would be possible particularly where low level winds shift a tad more easterly or where initial strong updrafts tap vorticity along the surface boundary. High res 4km NAM has isolated storms developing across eastern Las Animas and southwest Otero counties which move eastward across Bent, Prowers and Baca counties during the afternoon. Another area of convection develops along/north of the Palmer Divide where low level helicities should be a tad better. So these will be the areas to watch for severe weather potential tomorrow afternoon. Farther to the west, thunderstorms will be more isolated and high based with lightning and gusty winds the primary threats. Temperatures tomorrow will be around 10 degrees cooler across the southeast plains behind the front, to similar to a degree or two cooler out west. -KT .LONG TERM...(Friday night through Thursday) Issued at 339 PM MDT Thu May 25 2017 Unsettled meteorological conditions are anticipated during the balance of the longer term with primary concerns being pops/qpf, winds, temperatures and the potential for strong to severe thunderstorms as well as locally heavy rainfall at times. Recent longer term computer simulations, forecast model soundings and PV analysis indicate that several upper disturbances will interact with north-northeasterly surface surges over the forecast district at times. At this time, it appears that the highest potential for more widespread locally heavy rainfall and stronger to possibly severe thunderstorms should be noted Saturday and Monday(favoring eastern sections), although the time-frame from Friday evening into next Thursday has to potential to experience active conditions at times over many locations(primarily during the afternoon and evening hours). Generally below seasonal later May maximum temperatures are anticipated from Saturday into Tuesday, with maximum temperatures then expected to run near to slightly above later May climatological averages by next Wednesday and Thursday. In addition, minimum temperatures are projected to hover near to slightly above later May climatological averages during the duration of the longer term. Finally, the highest potential for stronger gradient winds over the forecast district should be experienced Friday night. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 339 PM MDT Thu May 25 2017 Gusty southwest winds gusting up to 35 kts will continue at all three terminals through the early evening. A cold front will bring a northwest to north wind shift at KCOS between 23-00z...which will spread southward into the KPUB taf site around 01z. Could see gusts in the 25-30 kt range behind the front for a couple hours after frontal passage this evening. Some patchy VFR stratus may develop towards morning across portions of the plains as winds shift out of the east and southeast...particularly in the KCOS area. These should dissipate by late morning with thunderstorms developing during the afternoon in the vcnty of KCOS. KALS and KPUB should see winds increase out of the south then southwest during the day with gusts up to 25-30 kt range by afternoon. -KT && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...LW