Marine Weather and Tide Forecast for Barry, IL

SHORT TERM
(Through Late Monday Night)
Issued at 257 PM CDT Sun Jun 7 2026

An upper-level low will continue to slowly migrate northeastward across the Mid-Mississippi River Valley through late Monday, providing episodic showers and thunderstorms across the CWA as lobes of associated mid-level vorticity and/or MCVs rotate cyclonically around the parent low. Due to the broad/ill-defined large-scale forcing and influence of previous rounds of showers and thunderstorms, CAMs and model guidance as a whole have struggled to come into agreement on the exact evolution of the upper-level low and resulting timing and coverage of showers and thunderstorms. On Monday afternoon/evening, HRRR membership has the greatest coverage shifting to along/east of the Mississippi River or beneath and downstream of the upper-level low. Although mid-level heights will be unfavorably rising Monday night, a lingering diffuse boundary has been indicated by some model guidance to exist Monday night along with potential interaction from a LLJ in addition to an upstream MCS or MCV tracking along that boundary early Tuesday morning. This evolution results in an increasingly uncertain forecast in terms of showers and thunderstorms, especially Monday night through Tuesday morning with a wide range of scenarios possible include those with very little or only isolated showers and thunderstorms.

With precipitable water flirting with 2" (99th climatological percentile) and deep warm cloud depths combined with kinematic profiles favorable for some organization of thunderstorms into clusters or small MCSs with training and backbuilding, locally heavy rainfall continues to be a concern through Monday night. Confidence in the threat of flash flooding has increased sufficiently to issue a Flood Watch for portions of central MO where multiple rounds of heavy rainfall are likely on top of 1 to 3" of rain that fell and has moistened soils. Elsewhere, we are missing this preconditioning of soils, lowering confidence in flash flooding at this point, especially considering a lack of coherent or consistent high-QPF signal in CAMs.

In addition to heavy rainfall there is also a low threat of severe thunderstorms this afternoon/evening and again on Monday. The latest SPC mesoanalysis depicts 1000 to 1500 J/kg MLCAPE including 100+ J/kg 0-3 km CAPE and 20 to 25 kt effective wind shear along with just enough low-level hodograph curvature to support a low, brief tornado or isolated damaging wind threat with a potential low- topped, transient supercell. However, the more favorable environment is across southwestern and southern MO. On Monday, the environment is significantly more variable with wind shear magnitude and hodograph structure sensitive to both the presence of a potential remnant MCV from overnight thunderstorms in southwestern MO/southeastern KS and arrival of a mid-level jet streak on the heel of the upper-level low. HRRR joint probabilities of 1000+ J/kg SBCAPE and 25+ kt deep-layer wind shear are greatest (50 to 70 percent) late Monday afternoon along/west of the Mississippi River, but the best overlap with stronger large-scale forcing appears to be across southeastern MO. However, confidence is low in the placement.
At least isolated damaging winds are possible, with a low tornado threat possible if wind shear sufficient for supercells is realized.

With regards to temperatures, early day cloud cover and showers and thunderstorms at times are expected to keep high temperatures on Monday in the 80s F. On Tuesday, there could be some morning cloud debris or lingering showers or thunderstorms, but an upper-level ridge axis shifting overhead will favor increasingly dry conditions and scattering of any cloud cover. With low-level southerly flow will also act to warm 850-hPa temperatures to near the 99th climatological percentile, supporting high temperatures in the upper 80s to low-90s F. With dewpoints well into the 70s F, ensemble model guidance has 30 percent probabilities of 100+ F heat index values during the afternoon and evening.

Pfahler

LONG TERM
(Tuesday through Next Sunday)
Issued at 257 PM CDT Sun Jun 7 2026

Global model guidance is trending toward a slightly quicker eastward shift/break down of the ridge as upper-level troughing takes place across the Northern Plains. This evolution has led to slightly cooler temperatures on Wednesday, but confidence is still high that it will be the warmest day of the week with much of the CWA seeing high temperatures in the 90s F given an approaching 850-hPa thermal ridge and potential downsloping of low-level southwesterly flow off the Ozark Plateau. Despite being warmer on Wednesday, dewpoints may tend to diurnally lower during peak heating, decreasing confidence that heat index values will be much higher than Tuesday. Model guidance is consensus that a shortwave trough rounding the broader longwave trough will force a cold front into the CWA sometime Thursday, providing another opportunity for showers and thunderstorms along with cooling temperatures closer to average.
However, this front may waver across the Mid-Mississippi River Valley into the upcoming weekend, prolonging chances of showers and thunderstorms.

Pfahler

AVIATION
(For the 18z TAFs through 18z Monday Afternoon)
Issued at 1230 PM CDT Sun Jun 7 2026

This TAF period will continue to be plagued by episodic rounds of showers and thunderstorms across the region, with confidence slightly higher in a round this afternoon and another tonight.
However, there is uncertainty in the exact timing and spacial extent of each round with PROB30 groups serving as the most likely times and terminals for impact. Showers and thunderstorms will be capable of as low as IFR visibilities and gusty winds. At least low chances of showers and thunderstorms will continue through Monday evening.
Aside from precipitation, MVFR ceilings are expected across portions of the area Monday morning, eventually lifting through the day.

Pfahler

LSX WATCHES/WARNINGS/ADVISORIES
MO...Flood Watch through Monday afternoon for Boone MO-Callaway MO- Cole MO-Moniteau MO-Osage MO.

IL...None.