####018003858#### FZPQ50 PGUM 160631 SRFGUM Surf Zone Forecast for the Mariana Islands National Weather Service Tiyan GU 431 PM ChST Fri May 16 2025 .DISCUSSION...There will be a moderate risk of rip currents along east facing reefs for the next several days, with a low risk along all other reefs. Little change is expected through the weekend. $$ GUZ001-MPZ001>003-162200- Guam-Rota-Tinian-Saipan- 431 PM ChST Fri May 16 2025 36 hour Surf Zone Forecast for the Marianas from 600 PM Friday through 600 AM Sunday .TONIGHT... Rip Current Risk.....Moderate *. Surf Height North facing reefs............2 to 4 feet. East facing reefs............5 to 7 feet. South facing reefs............1 to 3 feet. West facing reefs............Around 1 foot. Swell/Period Primary swell................East at 3 to 5 feet. Primary period...............8 seconds. Water Temperature Ritidian buoy..........85 Degrees. Winds...............East at 10 to 20 mph. .SATURDAY... Rip Current Risk.....Moderate *. Surf Height North facing reefs............2 to 4 feet. East facing reefs............5 to 7 feet. South facing reefs............1 to 3 feet. West facing reefs............Around 1 foot. Swell/Period Primary swell................East at 3 to 5 feet. Primary period...............8 seconds. Max Heat Index.........Around 97. Winds...............East at 10 to 20 mph. .SATURDAY NIGHT... Rip Current Risk.....Moderate *. Surf Height North facing reefs............2 to 4 feet. East facing reefs............5 to 7 feet. South facing reefs............1 to 3 feet. West facing reefs............Around 1 foot. Swell/Period Primary swell................East at 3 to 5 feet. Primary period...............8 seconds. Winds...............East at 10 to 20 mph. Tide information for the next 36 hours... At Apra Harbor, Guam... Low tide -0.1 feet at 4:00 PM Friday High tide 2.3 feet at 11:36 PM Friday Low tide 1.9 feet at 4:54 AM Saturday High tide 2.2 feet at 9:00 AM Saturday Low tide -0.1 feet at 4:42 PM Saturday High tide 2.4 feet at 12:30 AM Sunday Low tide 1.9 feet at 5:42 AM Sunday At Rota Island... Low tide -0.1 feet at 3:54 PM Friday High tide 2.2 feet at 11:33 PM Friday Low tide 1.7 feet at 4:48 AM Saturday High tide 2.1 feet at 8:57 AM Saturday Low tide -0.1 feet at 4:36 PM Saturday High tide 2.2 feet at 12:27 AM Sunday Low tide 1.8 feet at 5:36 AM Sunday At Tinian Island... Low tide -0.1 feet at 3:42 PM Friday High tide 1.7 feet at 12:18 AM Saturday Low tide 1.6 feet at 4:24 AM Saturday High tide 1.7 feet at 7:48 AM Saturday Low tide -0.1 feet at 4:30 PM Saturday High tide 1.7 feet at 1:06 AM Sunday Low tide 1.5 feet at 5:18 AM Sunday At Tanapag Harbor, Saipan... Low tide -0.2 feet at 4:05 PM Friday High tide 2.2 feet at 12:23 AM Saturday Low tide 1.8 feet at 5:17 AM Saturday High tide 1.9 feet at 8:24 AM Saturday Low tide -0.2 feet at 4:49 PM Saturday High tide 2.2 feet at 1:07 AM Sunday Low tide 1.8 feet at 6:37 AM Sunday * Low Risk of rip currents - Strong currents can still occur near jetties and reef channels. Always have a flotation device with you in the water. Moderate Risk of rip currents - Wave conditions support stronger or more frequent rip currents. Always have a flotation device with you in the water. High Risk of rip currents - Large waves will produce strong rip currents, especially along narrow reefs and beaches. If caught in a rip current, swim parallel to the beach rather than against the current. $$ ####018004579#### FXUS61 KILN 160632 AFDILN Area Forecast Discussion National Weather Service Wilmington OH 232 AM EDT Fri May 16 2025 .SYNOPSIS... Warmer temperatures will be observed through the end of the week. A series of disturbances will bring the potential for thunderstorms mainly late in the day into tonight and again Friday and Friday night. Cooler temperatures and drier weather will follow heading into the weekend. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... Mid-level ridge axis centered over the middle Ohio Valley will be shunted to the east late tonight as the first in a series of shortwaves arrives from the upper Midwest. Despite favorable instability and wind shear for thunderstorms, forcing will focused to the north of our CWA. Severe parameters are robust in a few of the latest CAMs. Therefore, will keep PoPs in the chance range (highest in the north and west) while closely monitoring any robust updrafts that can take advantage of the parameter space. If storms develop, all hazards will be possible. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/... After a lull in the active weather Friday morning, a more significant shortwave will approach the region during the afternoon. This time, a warm front will initially be the focus of the forcing, starting across the Tri-State during the evening and lifting through the rest of the CWA just after midnight. Instability across our southern counties will peak around 3000J/kg from late afternoon into the evening, while bulk shear is likely to exceed 50 knots in the evening. Some CAMs show a warm air advection wing lifting northeast with potential discreet supercells. Behind this, it's likely a QLCS will bring the threat of damaging winds and a line- embedded tornadoes late. There is also the possibility that the line could be slowed across the south with west to east training convection bringing the threat of flash flooding. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Closed low will track across the Great Lakes to start the period which will push a cold front through the area. Most likely, this will come through dry, but there could be enough deep forcing to allow for some showers along the northern tier of the forecast area. Ridging will build in for Sunday and Monday resulting in dry conditions with temperatures near or even slightly below normal. The mid level pattern becomes blocky again towards midweek with the usual uncertainties as the flow transitions. At this point, it appears most likely that a closed low will move out of the central Plains and track into the Ohio Valley while getting absorbed into another closed low retrograding across eastern Canada. This will bring another period of wet weather. Highs will remain slightly below normal with lows closer to normal. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... Mid level shortwave and associated thunderstorm complex is moving thru the Great Lakes. Convection has been inhibited further south into ILN/s area due to a cap. Some of the model forecast soundings show this cap diminishing with the potential for a few showers or perhaps an elevated thunderstorm toward sunrise. Coverage and likelihood of development are too low to mention in the TAF forecasts at this time. In the warm sector strong instability is expected to develop today with SBCAPE of 2500-3500 J/kg. This combined with increasing deep layer shear will lead to the threat for strong to severe storms late in the day into this evening. CAM solutions continue to show a very good signal for storm development to our west - which organizes as it moves eastward into the Ohio Valley. This complex of strong to severe storms is expected to impact the TAF/s late in the day into this evening. Exact timing is still somewhat uncertain but the greatest impacts look to occur as early as 22Z across KCVG and KLUK thru about 03Z at KCMH/KLCK. All severe weather hazards are possible from these storms. Surface winds increase out of the southwest with sustained winds of 10-15kts and gusts up to 25 kts. Expect VFR conditions until storms develop with LIFR conditions in storms. OUTLOOK...Thunderstorms are possible through Saturday. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...None. KY...None. IN...None. && $$ SYNOPSIS...AR NEAR TERM... SHORT TERM... LONG TERM... AVIATION...AR ####018009031#### FXUS62 KRAH 160632 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 230 AM EDT Thu May 15 2025 .SYNOPSIS... Upper level disturbances moving atop an upper level ridge building across the SE US will support mainly diurnal showers and storms and unseasonably hot temperatures to end the work week. A series of cold fronts will move through the region over the weekend. && .NEAR TERM /THROUGH TONIGHT/... As of 950 PM Thursday... The Severe Thunderstorm Watch has been cancelled for the entire forecast area. Showers and thunderstorms across the eastern portion of the forecast area have fallen apart. However, several runs of the HRRR show the potential for some showers to move into western portions of the forecast area late tonight toward sunrise, and have added some slight chance pops to account for that. In addition, some patchy fog cannot be ruled out considering there has not been a change in airmass and there is plentiful low level moisture. Lows will be in the mid and upper 60s. && .SHORT TERM /FRIDAY AND FRIDAY NIGHT/... As of 230 PM Thursday... * A conditional risk of severe storms will exist across the nrn half of cntl NC on Fri, based on lower predictability, mesoscale influences from upstream convection across the lwr OH Valley today- tonight. 12Z guidance this morning continues to highlight an uncertain forecast wrt to convection Friday. An upstream, decaying MCS is still forecast by several models (e.g. NamNest, HRRR, NSSL) to cruise across the mountains and foothills early Friday morning. Strong sfc gusts (possibly 35 to 45 kts) associated with it's cold pool still look plausible early to mid Friday morning across the northern Piedmont. This scenario would favor less convective potential later Friday afternoon, as lingering cooler air and cloud debris limit sfc heating across northern areas. Alternatively, the FV3 and ARW CAMs continue to simulate the morning MCS further north into Virginia. This scenario would favor strong heating across all of central NC and the development of strong CAPE by Friday afternoon. Any convection that develops in this environment would favor explosive updrafts and supercells capable of large hail and damaging wind gusts. Given this potential scenario, the SPC has introduced a Marginal Risk for severe storms over our northern tier of counties. However, given some models limit afternoon convection, decided to maintain just slight chance PoPs across generally northern locations Friday afternoon and evening. During the overnight hours, yet another round of upstream, decaying MCSs are forecast to move into the mountains and foothills through sunrise. Like clockwork, there is little guidance consensus on the evolution of these features. However, its worth noting that some CAMs do indicate the potential for another round of strong sfc gusts embedded within associated cold pools early Saturday morning. Worth watching for sure. && .LONG TERM /SATURDAY THROUGH THURSDAY/... As of 355 PM Thursday... The mid/upper low and occluded surface low will track east across southern Ontario/Quebec and the Great Lakes on Saturday and Saturday night, dragging a cold front to the south that will pass through central NC during the afternoon and evening. Model guidance indicates an MCS will approach from the TN Valley on Friday night, but weakening significantly as it crosses the Appalachians and approaches central NC on Saturday morning, with outflow surging out ahead of it. Models struggle with depicting the strength and timing of these MCS's, especially this far out, and that will be critical for the severe storm threat later in the day. A weaker MCS that passes through earlier on Saturday would favor more daytime heating and destabilization compared to vice versa. The NAM Nest is the only high-res guidance that goes out this far, and it does depict ample instability resulting in a broken line of showers and storms developing along the cold front from Saturday mid-afternoon into the evening. However, lower-res guidance is mostly dry, and moisture with the front does not look impressive, as the flow aloft is from a westerly direction. Furthermore, we will only get weak upper forcing with the low tracking so far to our north. GFS/ECM/CMC ensemble mean QPF continues to trend drier and is less than a tenth of an inch. So while convective coverage is still unclear, think it should be pretty isolated, and only have slight to low chance POPs. Still, there is a conditional threat of a few strong to severe storms with large hail and damaging winds developing along and ahead of the front, as surface-500 mb bulk shear will be as high as 40-50 kts. Also can't rule out some strong cold pool induced wind gusts with what is left of that MCS on Saturday morning. Saturday's temperatures may be kept down in the morning by outflow and clouds from the system, but we should still get good surface heating in the afternoon as clouds break and we get strong SW winds ahead of the front (gusting up to 20-30 mph even outside of any storms). So forecast highs are still mid-80s to lower-90s, not quite as warm as Friday, but heat indices in the mid-to-upper-90s will still be possible in the SE. The mid-level flow will turn NW from Sunday into Tuesday, as we are caught between the low slowly drifting east over New England and the Canadian Maritimes and ridging that strengthens and builds east from the MS Valley to the Deep South and TN Valley. At the surface, a backdoor cold front looks to move through central NC on Sunday night. This front then looks to lift back slowly north on Monday and Tuesday, and latest guidance has trended toward the front lingering more on top of our region instead of to our SW. Precipitation chances could be enhanced by a series of MCS's that move overtop the ridge and through the southern Mid-Atlantic. So expect gradually increasing shower and storm chances each day, but there is still plenty of uncertainty. The next mid/upper low will move east from the Central Plains on Tuesday, but models disagree on the pattern evolution after. The GFS picks it up by a northern stream low over the Great Lakes and is more progressive, while the ECMWF keeps the systems separate and thus hangs them back longer. This will have a big impact on precipitation chances as well as temperatures, but it looks like an associated cold front will move through sometime Wednesday or Thursday. For now have POPs increasing to high chance to likely on Wednesday, decreasing somewhat on Thursday as the GFS and most of its ensembles are dry by then while the ECMWF and CMC are still wet. As cool high pressure extends south from the Hudson Bay into the Eastern US, expect at least slightly cooler temperatures from Sunday into Tuesday with highs mainly in the 80s and lows in the upper-50s to mid-60s. Dew points will be more tolerable compared to now, generally mid-50s to lower-60s. A sharp drop to below-normal temperatures should occur late next week once the Wednesday/Thursday cold front moves through. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... As of 230 AM Friday... 24 hour TAF period: An isolated shower/storm or two remains possible overnight. Otherwise, with the exception for some variable restrictions at fog prone KRWI, all remainder TAF sites should remain VFR through daybreak. Forecast confidence is lower than normal wrt to storm potential this afternoon and evening. Upper level disturbances spilling atop a strong upper level ridge in place across the region may support isolated to scattered storms across the northern portions of the forecast area this afternoon and evening. Alternatively, the upper ridge could largely suppress/stifle compression, keeping the area free of convection. Should storms hold together, strong instability and shear would be conducive for strong wind gusts of 30-50kt+, hail and sub-VFR conditions for any northern TAF site(KINT, KGSO, KRDU, and KRWI)that takes a direct hit. Given the uncertainty, will omit any mention of storms and restrictions at this time. But a period of storms/restrictions may need to be added with later TAF issuances. Outlook: Chances for diurnal isolated to scattered showers and storms will continue through much of the period. Morning fog and low stratus will be possible each morning, especially in areas that received significant rainfall the previous day. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...CBL NEAR TERM...Green SHORT TERM...Luchetti LONG TERM...Danco AVIATION...CBL ####018007115#### FXUS62 KMHX 160632 AFDMHX Area Forecast Discussion National Weather Service Newport/Morehead City NC 232 AM EDT Fri May 16 2025 .SYNOPSIS... Inland troughing is expected today, followed by a cold front passage on Saturday. High pressure then builds in late in the weekend and into early next week. && .NEAR TERM /TODAY/... As of 200 AM Friday... KEY MESSAGES - Another conditional risk of severe weather late - Humid with above normal heat Yesterday's severe thunderstorms formed on the periphery of a stout mid/upper level ridge that has been anchored over the Southeast U.S. That ridge is forecast to build a bit further north today, with an even stronger cap expected compared to yesterday. Meanwhile, heating of a moist boundary layer beneath a stout EML plume will once again support an area of moderate to strong instability over ENC, with MLCAPE reaching, or exceeding, 3000j/kg. The majority of deterministic guidance suggests a moderate to strong cap will remain in place through the day, which would be a significant limiting factor for sustained deep convection. Not all guidance shows this, though. Adding to the limitations is the mid/upper ridging near the region, providing an area of large-scale subsidence. The effect of ridging may be short-lived, though, as guidance suggests the ridge will flatten late in the day as an upper trough pivots east across the Ohio Valley. What appears likely is that there will be several clusters of severe thunderstorms well upstream associated with the upper trough. Guidance differs on the evolution of these clusters of storms, but upscale growth, and the upper pattern, favors one, or more, MCS' translating east from the OH/TN Valleys to the Mid- Atlantic/Carolinas. This convection will encounter the strong cap mentioned above, making it unclear whether or not convection can survive all the way to ENC. Should sufficient erosion of the cap occur, as some guidance suggests, there would be sufficient shear and instability to support MCS maintenance and an attendant risk of damaging winds. Some hail could occur as well, but wind appears to be the primary risk. Stay tuned for updates through the day on this potential. For now, we'll continue to hold with a low chance of thunderstorms focused north of HWY 70. This is also where the cap may be the "weakest", and where the greatest risk of severe weather would be focused. Otherwise, moderate to strong heating, plus warming thicknesses, beneath the ridge should support highs reaching the 90s inland, and 80s along the coast. With dewpoints in the 60s and 70s, this should allow the "feels like" temperature to reach the mid to upper 90s for much of the area. && .SHORT TERM /TONIGHT/... As of 200 AM Friday... KEY MESSAGES - Conditional severe thunderstorm risk may linger into tonight The mid/upper level ridge over the region will continue to get flattened tonight as an upper trough shifts east from the OH Valley to the Northern Mid-Atlantic. Guidance suggests multiple MCS' may be ongoing upstream of ENC, and the environment may support some continuation of this activity into the eastern Carolinas with an associated risk of gusty to damaging winds. Given the expectation of a strong cap in place, any MCS may tend to weaken with time as it approaches the area, but stay tuned for updates on this potential. && .LONG TERM /SATURDAY THROUGH THURSDAY/... As of 0400 Thursday... Hot again on Saturday in downsloping flow, push highs into the lower or mid 90s with dew points still in the upper 60s. Heat indices in the upper 90s FRI, mid 90s SAT. Westerly flow intersecting the sea breeze could produce isolated storms during the afternoon with a slight uptick in rain chances during the evening as a cold front approaches the area, crossing overnight. Followed by a secondary backdoor front end of the weekend. Quiet and relatively cool early through midweek ahead of the next vertically stacked low to dig toward the Carolinas late week. && .AVIATION /07Z FRIDAY THROUGH TUESDAY/... SHORT TERM /through 06z Saturday/... As of 130 AM Friday... KEY MESSAGES - Low confidence TSRA risk over the next 24 hrs Mid to upper level ridging will be nosing into the area today, with some subsidence and a fairly stout cap. It will be sufficiently unstable for TSRA, but ridging and the cap calls into question whether or not TSRA will impact ENC over the next 24 hrs. For now, we'll keep a VFR TAF going for all terminals given the low confidence forecast. The focus through Friday night will be TSRA well upstream across the TN and OH Valleys. Some guidance suggests this activity will survive the trek across the Appalachians and the piedmont of the Carolinas, eventually reaching ENC late Friday afternoon or Friday evening. Should this scenario play out, the environment appears supportive of strong wind gusts of 30-50kt+ and sub-VFR conditions. Stay tuned for updates with later updates in case confidence were to increase regarding the TSRA potential. LONG TERM /Saturday through Tuesday/... As of 0400 Thursday...Shower chances decrease late this week and into the weekend, but isolated to scattered coverage will be possible each day (primarily during the afternoon). && .MARINE... SHORT TERM /through tonight/... As of 130 AM Friday... KEY MESSAGES - Breezy winds and elevated seas to continue through tonight - The thunderstorm risk appears generally lower through tonight A modest pressure gradient across the area this morning will tighten later today through tonight, supporting a continuation of modest southwesterly flow (10-20kt) across area waters. For the coastal waters, this will keep seas elevated (3-5 ft). In general, the thunderstorm risk appears much lower today compared to yesterday. That said, at least some guidance suggests a cluster of thunderstorms may impact the central and northern waters later today through this evening. Should this occur, there would be an increased risk of 30-50kt+ wind gusts. LONG TERM /Saturday through Tuesday/... As of 0400 Thursday...Boating conditions deteriorate Saturday ahead of the next cold front to cross area waters leading to probable SCA conditions in SWerly 15-25kt winds SAT afternoon and evening. Secondary backdoor front sinks S across waters late Sunday. High pressure builds in with Nerly surge late SUN night/MON AM. Generally 10-15kt winds slowly through early week N-NEerly Tuesday becoming Eerly Wednesday as offshore high departs SEward and next low approaches from the W. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...None. MARINE...None. && $$ SYNOPSIS...MHX NEAR TERM...RM SHORT TERM...RM LONG TERM...CEB/RJ AVIATION...RM/CEB MARINE...RM/CEB