Marine Weather and Tide Forecast for Inland, NE

DISCUSSION
Issued at 445 AM CDT Sun Oct 13 2024

Gone are the times of daily highs in the 70s and 80s, at least for now, as the upper pattern has become much more amplified thanks to deep trough digging S out of Canada and into the Great Lakes. This trough will force our low level flow to be much more Nrly next few days, compared to the persistent mild S/W flow as of late. While the brunt of the really chilly air will remain primarily N/E of the local region, our forecast has steadily trended cooler over the past few days such that highs are now mostly forecast to be in the 60s to near 70F today and Monday, and perhaps only 50s to lower 60s on Tue behind a reinforcing shot of Canadian air.

It's going to feel much more "fall-like" next few days, and that includes the potential for significantly cooler mornings and more widespread frost and freeze concerns. Local climatology shows our upcoming likely frost and possible freeze dates are actually pretty close to "normal", or just a few days late. Only changes made to the ongoing Freeze Watch and Frost Advisory for Sun night into Mon AM was to add Smith and Rooks Cos in north central KS. Would've liked to convert the watch to a Freeze Warning over at least our N third where latest NBM places probabilities for sub-32F lows at around 70-90%...but collaboration precluded this change and thus it'll be on the day shift to make the headline adjustments. Worth noting that it appears the probs are being driven higher by the MOS guidance that is easily 10+ deg colder than raw model output. Personally, tend to favor the colder side of guidance as models show very light winds and clear to mostly clear skies tonight - conditions that are ideal for strong radiational cooling. Also, ongoing dry soils and worsening drought conditions often lend to more aggressive cooling at night, which is something we noted locally about a week to 10 days ago. While the NBM has improved recently, still worried it's hanging onto too much warm-season bias-correction - likely driven by crop ET ("corn sweat) - which helps to keep the overnight lows warmer during the main growing season. Well, obviously we've lost the ET and have otherwise been very dry lately, and these changes have likely occurred faster than what the bias- correction is designed to handle.
Bottom line, I think the MOS guidance is onto the right trend at least as it does not have this kind of bias-correction built into it...so I wouldn't be shocked if the Freeze Watch is converted to a Warning, and perhaps even expanded southward a couple counties. Think most of our KS zones are safely in the "frost or nothing" category, with our N zones such as around Ord safely in the "hard freeze" category...with the remaining areas, including the Tri- Cities, generally around 29-34F.

NBM freeze probabilities, along with most raw model output temps, suggest slightly warmer conditions for Mon night into Tue AM, likely due to stronger E/NE sfc winds around 5-9kt associated with a reinforcing "back door" cold front. This front is also why Tuesday has trended cooler to now primarily 50s for highs in Neb zones, and low 60s in our Kan zones. Not surprisingly, this trend has bled into Tue night-Wed AM, which now also looks like a strong candidate for widespread frost and areas of sub- freezing low temps. The return flow now doesn't look to kick in until daytime Wed in which highs attempt to rebound to the 60s.

More pronounced warmup remains on track for Thu-Fri time frame.
However, similar to 24 hours ago, guidance still has some variability in overall timing and magnitude of incoming late week trough, which will dictate the strength of warm air advection and exact warmth preceding it. If anything, it seems as though there has been a slight slowing trend and convergence towards a Fri PM fropa. This could keep the hottest readings to our W on Thu, but bring Fri aftn into play for warmer and windier conditions. 00Z ensemble cluster analysis reveals that the warmest cluster is largely driven by the GEFS and GEPS model cores, with each core contributing about 30% of it's members to this solution, or about 20% of all ensemble members. Only 8% of the EPS members fit this warmer cluster. The other three clusters are much more closely aligned in terms of H5 upper height pattern and resulting sensible weather at the surface, which suggests a solid warmup into the upper 70s to mid 80s is favored, and that the GEFS/GEPS members that make a run at record highs in the lower 90s are more of an outlier at this time. Also similar to 24 hrs ago, it still appears that regardless of the exact front timing, we're likely going to be looking at a solid 24-48hr time frame of strong Srly sfc winds.
This does not bode well for fire weather concerns, which are discussed in greater detail below.

Eventually the cold front will work it's way into the region, and at some point begin to tap into incr deep layer moisture advection. Assuming a Fri aftn/eve timing of front, it could be close as to if the entire forecast area will indeed have good rain chances. There has been a trend in the ensemble guidance of keeping the heaviest rain axis just to our E/SE...which often doesn't bode well of at least our W/NW zones as the cut-off to no rain is often pretty sharp. As such, we're already seeing a tightening in the probs for 0.5", or more, with EPS showing 50-60% in our far S/SE, but only 10-30% in our W/NW zones. Could envision some higher chances of the front slows down more, but this could also keep fire conditions higher locally into Fri, as well. Also, what once looked like a solid 24-48hr window for rain has diminished to only ~12hrs as the overall pattern looks to remain more progressive. Obviously not a great trend for those looking for much-needed moisture, but perhaps the bright side is that it looks like primarily Pacific-based airmass behind this system, so still some pleasant highs in the 60s-70s for next weekend into the following week.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/
Issued at 618 AM CDT Sun Oct 13 2024

For KGRI/KEAR Airports:

VFR through the period with only off and on high clds. Lgt Nrly winds currently will incr after sunrise and bec brzy by mid to late AM with sustained speeds 14-17kt, and gusts around 25kt.
Lgt and vrbl winds return around sunset. Confidence: High.

FIRE WEATHER
Issued at 455 AM CDT Sun Oct 13 2024

Today: Still looking at marginally near critical fire weather conditions today, though perhaps over a larger region than appeared 24 hours ago. Would attribute this expansion to broader shield of 20-25 MPH wind gusts on the backside of a deepening trough over the Great Lakes. While the wind field looks more expansive, this has also supported a slight downward trend in high temps...so it still appears that RHs will remain above 20%, with the actual time frame of near-critical RHs 20-25% only being from about 3-6PM.

Next week: Fire concerns are elevated, but probably not quite to "near critical" levels during the early part of the new work week. Min RHs will dip into the 20-30% range each afternoon Mon and Tue, but winds look to remain light.

Wednesday will mark the beginning of a period of potentially enhanced fire weather. Return Srly flow will begin to incr by Wed aftn, and with slightly warmer air temperatures, could be looking at fairly widespread min RHs in the 20s. Fire weather concerns will likely peak on Thu as model guidance is in pretty good agreement in strong Srly low level flow ahead of the next cold front, with gusts easily in the 30-40 MPH range, possibly even 40-45+, in spots. As noted above, there is still some uncertainty in location/magnitude of low level thermal ridge ahead of the front - which will determine exactly where the core of lowest RHs sets up. Still think Thu stands a decent chance for being a higher-end type of fire day, particularly for our KS zones. Usually the forecast trends hotter, drier, and windier as we get closer, and we're already at a potent combination and it's only day 5-6. Fri is not a day to write off completely, either, as expect a continuation of the strong wind. The difference from Thu could be stronger moisture return and possibly min RHs mainly above 30 percent, but with as dry as we've been, maybe this doesn't matter as much as the wind.
Hopefully we can get some much needed moisture along the front Fri PM, though it may also come at the risk of some lightning.

GID WATCHES/WARNINGS/ADVISORIES
NE...Frost Advisory from 1 AM to 9 AM CDT Monday for NEZ041-048-049- 062>064-072>077-082>087.
Freeze Watch from late tonight through Monday morning for NEZ039-040-046-047-060-061.
KS...Frost Advisory from 1 AM to 9 AM CDT Monday for KSZ005-006-017.