Marine Weather and Tide Forecast for Raymer (New Raymer), CO

UPDATE
Issued at 1015 AM MDT Wed Apr 23 2025

North to northeast low level flow behind this morning's cold front is gradually increasing moisture over the area. Dew points have climbed into the 30s with some lower 40s over the northeast plains. Stratus clouds have formed over the northeast plains.
These clouds will below slow to burn off and may not over far northeast Colorado as moisture and cooler air is advected into the area. Increased cloud cover and lowered highs over the northeast plains.

Still on track for few strong/severe storms late this afternoon and evening. With cooler and more stable air under the low clouds over northeast Colorado, the best for the stronger storms will be over to the south across the Palmer Divide, eastern Adams/Arapahoe Counties, southern Washington and Lincoln Counties. These areas are expected to see better heating leading to increased instability. SBCAPE to climb to ~1000 (J/kg). As these storms progress northeast they will weaken some, but widespread showers and thunderstorms are expected over the northeast plains.
Increased PoPs for this, and also made minor timing adjusts to the forecast grids.

SHORT TERM /Through Tonight/
Issued at 319 AM MDT Wed Apr 23 2025

A weak cold front is moving across the Denver metro this morning, with a modest increase in low-level moisture behind it. Moist southwesterly flow aloft is well established at this point and should continue for the next few days.

Gradual sfc moisture advection is expected to continue today, with guidance bringing mid 40s dew points into the eastern plains by this afternoon. A developing lee cyclone over southeastern Colorado should lead to strengthening easterly upslope flow through the day, with MUCAPE values increasing to 500-1000 J/kg where daytime heating is strongest. It's not surprising that this pattern will lead to widely scattered showers and thunderstorms this afternoon, especially with a weak shortwave trough moving across the region. With fairly impressive deep layer shear (35-45kt) and slightly cyclonically curved hodographs, a couple of supercells would be capable of producing some hail/wind, despite the fairly modest instability. The main limiting factor today will be the presence of a fairly substantial cap. However, most CAMs still develop a couple of storms east of I-25, generally favoring the Palmer Divide/Limon and far northeastern Colorado near the Nebraska panhandle.

At least a few showers and storms will continue into the evening and overnight hours, as moist/northeast surface flow persists, allowing for at least some marginal elevated instability. The best chances of precipitation overnight will again be over the northeast plains.

LONG TERM /Thursday through Tuesday/
Issued at 319 AM MDT Wed Apr 23 2025

The forecast pattern will stay active to end the week, though chances of showers/storms become more conditional.

The aforementioned moist advection/upslope will likely lead to widespread stratus across the plains on Thursday morning. The evolution of the stratus Thursday will be the key to how much surface heating/destabilization can occur before a fairly strong cold front pushes through the region during the afternoon/evening. If we manage to reach the mid/upper 60s, there's a fairly favorable setup for another round of thunderstorms in the afternoon, with a few strong to severe storms possible in a good CAPE/shear regime.
That corridor would likely shift a little west compared to today... closer to the I-25 corridor. Both the NCAR MPAS ensemble and the overnight extended HRRR run would both support at least a marginal severe threat. On the other hand, if temperatures end up in the upper 50s to low 60s there may be just a few showers and an isolated, non-severe thunderstorm.

Similarly, any convection on Friday would likely depend on the evolution of the numerous features from the prior day. Guidance is in better agreement overall that this will be the quietest of the three days, with little to no instability to work with in the post frontal airmass. There'd also be some stratus/fog potential to contend with in the first half of the day.

By the weekend, stronger southwesterly flow is expected to develop as a upper trough axis approaches. With warming mid-level temperatures and increasing downslope, forecast highs will return to well above normal values (mid/upper 70s). The increasing flow will also lead to some fire weather concerns, especially on Sunday.

The upper trough axis should slide through the region sometime early next week. Guidance tonight was a little bit further south with the main shortwave in this period, with slightly cooler temperatures and more moisture returning by Monday or Tuesday. Too much uncertainty at this point to worry about the details, but at the very least it looks like an active pattern would continue.

AVIATION /18Z TAFS through 18Z Thursday/
Issued at 1133 AM MDT Wed Apr 23 2025

Low clouds have developed this morning over far northeast Colorado, in the FMM and AKO areas and northeastward. Even though the low clouds are progressing westward, they are expected to stay east of the Denver. Isolated to scattered showers and storms are expected to form after 21Z. Most numerous to the south of Denver. Outflow winds may result in a wind shift or two. Best chance for DEN to see a showers or storm is 23Z to 03Z. Low clouds will push into DEN tonight 05-08Z, with ceilings of 500-2000 feet. The low clouds persist through Thursday morning with scattering expected 18-19Z Thursday.

As far as winds go, northeast winds will continue to turn clockwise becoming and easterly direction 20-21Z. An outflow from thunderstorms to the south of Denver is expected to produce a south to southeast wind shift 23-02Z. Winds become light overnight and are expected to stay light into Thursday.

BOU WATCHES/WARNINGS/ADVISORIES
None.