California Central Valley and Coastal Growing Areas

Last 24 hours: Early December commonly brings cool, calm mornings with patchy radiation fog (tule fog) in the Valley and coastal light showers if a weak Pacific disturbance brushes the coast. Orchard floors are seasonally damp, aiding cover crop establishment; citrus zones focus on freeze monitoring on the coldest nights.

Implications: Fog can slow harvest logistics and spray windows in the morning; watch inversion conditions that limit drift control. Where showers occurred, soils remain tacky but manageable on well-drained ground.

Pacific Northwest (WA/OR/ID specialty crops and wheat)

Last 24 hours: This period often features maritime showers west of the Cascades, mountain snow building snowpack, and cooler, breezy conditions in the Columbia Basin. Winter wheat benefits from moisture; fieldwork windows are brief between bands.

Implications: Snow levels fluctuate with each wave; orchard and vineyard areas monitor for cold snaps on clear nights. Travel over passes may be impacted by snow and wind.

Southwest and Desert West (AZ/NM and SoCal deserts)

Last 24 hours: Typically dry with large diurnal ranges. Occasional high clouds may filter sun if Pacific energy passes to the north. Radiation freezes are a risk in low-lying fields on the coldest nights.

Implications: Excellent harvest and planting windows persist, but be prepared for frost protection on tender vegetables and nursery stock when winds decouple overnight.

Northern Rockies and High Plains (MT/WY/Western Dakotas)

Last 24 hours: Seasonal early-winter pattern with clipper-type systems bringing bursts of wind, light snow, and sharp temperature drops. Post-frontal air is dry with elevated fire weather on the warm side and patchy blowing snow on the cold side.

Implications: Livestock wind chill management remains a priority; any fresh snow improves soil moisture recharge but may briefly hinder transport.

Northern Plains and Upper Midwest (Dakotas/MN/WI/MI)

Last 24 hours: Behind passing fronts, lake-effect snow is common downwind of the Great Lakes; elsewhere, brisk and dry conditions promote grain drying. Cloud cover varies widely, influencing nighttime freezes.

Implications: Residual slick spots possible in snow belts; otherwise, cold, dry air favors equipment access with caution for ruts in previously wet fields.

Central and Southern Plains (NE/KS/OK/TX Panhandle)

Last 24 hours: Typical setup brings a windy, drier post-frontal environment aiding topsoil drying. Light, fast-moving showers may have skirted the eastern fringe; western grazing areas remain cool and dry.

Implications: Winter wheat benefits from moisture received earlier in the week; monitor for wind desiccation and blowing dust where cover is thin.

Corn Belt and Ohio Valley (IA/IL/IN/OH/MO)

Last 24 hours: Variable cloudiness with a tendency toward cooler, drier air after a front. Scattered light precipitation bands can leave damp topsoil east; west stays drier and breezier.

Implications: Short harvest and tillage windows open between systems; watch for fog formation overnight where soils are moist and winds lighten.

Delta and Mid-South (AR/MS/TN/LA)

Last 24 hours: Gulf moisture often feeds spotty showers along and ahead of weak fronts, with clearing and cooler, drier air trailing. Morning fog is common in river bottoms.

Implications: Brief wetting may slow field traffic on heavy clays; cooler, dry breaks favor post-harvest field prep.

Southeast (AL/GA/FL/Carolinas)

Last 24 hours: Early-December fronts frequently bring a band of showers followed by breezy, cooler conditions. Inland areas see patchy frost on the coldest nights; coastal zones stay milder with sea-breeze influences.

Implications: Citrus and winter vegetables should prepare for radiation frost on clear, calm nights inland; disease pressure eases with drier, breezier post-frontal air.

Northeast (PA/NY/NJ/New England)

Last 24 hours: Mixed precipitation is common with marginal temperatures; interior valleys tend to freeze overnight when skies clear. Lake-effect snow impacts the typical belts off Erie and Ontario after cold frontal passages.

Implications: Orchard and vineyard grounds see freeze-thaw cycles; mud and slick travel possible near snow bands.

Temperature

• West: Cool to seasonable along the coast; colder in the mountains. Nighttime inversions in interior valleys bring frost potential where skies clear and winds are light.
• Plains: Wide swings of 15–25°F over 24–48 hours are typical as fronts move through. Watch for brief warm-ups ahead of each system, then sharp cool-downs.
• Midwest/Great Lakes: Near to slightly below normal after frontal passages, with wind chills lowering livestock comfort; modest moderation before the next front.
• South (Delta/Southeast): Near normal days; multiple nights near or below freezing inland, especially in protected lows. Coastal plain remains milder.
• Northeast: Near to below normal, with freeze-thaw cycles and occasional subfreezing nights in interiors.

Precipitation

• Pacific Northwest and Northern California: Periodic light to moderate rain/snow with snow levels fluctuating; mountain snowpack builds. Short lulls between waves.
• Southwest deserts: Mostly dry; isolated showers possible if a disturbance dips farther south than usual.
• Northern Rockies/High Plains: Light snow events with clippers; localized blowing snow and wind.
• Central U.S.: One broader system likely brings a swath of light to moderate precipitation from the Central Plains into the Midwest/Great Lakes, with rain changing to wintry mix or snow on the back side in the north.
• Gulf Coast/Delta/Southeast: Scattered showers along frontal boundaries, generally brief; heavier pockets possible near the Gulf if moisture pools.
• East Coast/Northeast: Light to moderate precipitation with the main system; snow or mixed precipitation inland and higher elevations, rain near the coast; lake-effect snow in typical belts after colder air arrives.

Wind and Fieldwork Windows

• Plains: Breezy to windy on frontal days, providing rapid surface drying but elevating erosion risk where cover is sparse.
• Midwest: 1–2 short, workable windows for harvesting/tillage; strongest winds near and just behind fronts.
• Southeast/Delta: Light winds and stable conditions between fronts promote spraying and harvest; monitor for morning fog.
• West: Coastal and gap winds around each wave; mountain passes see periods of hazardous crosswinds and blowing snow.

Regional Outlook Highlights

California and the West

• Central Valley: Morning fog risk persists; frost possible in colder pockets. Short drizzle/light rain chances on weak systems. Plan spray operations for late morning to early afternoon when visibility and mixing improve.
• Coastal and Sierra Foothills: Intermittent light rain; avoid saturated slopes for machinery. Sierra snowpack gradually increasing—monitor access constraints.
• PNW: Repeated light precipitation supports winter wheat and cover crops; watch puddling on heavier soils and limited consecutive dry hours for field traffic.

Southwest

• Desert vegetables/citrus: Multiple nights with radiational frost potential in wind-sheltered fields; ensure irrigation/frost protection readiness. Daytime conditions remain favorable for harvest and growth.

Northern Rockies and Plains

• Expect at least one clipper bringing light snow and a sharp cooldown. Livestock cold stress periods align with the breeziest, post-frontal 24–36 hours.
• Winter wheat: Monitor for desiccation on exposed ridges; snow cover, where present, offers protection.

Central/Southern Plains

• Two distinct windows appear likely: a pre-frontal mild period and a cooler, breezy, drier stretch after passage. Use the latter for topsoil drying and grain conditioning.
• Watch for fire-weather concerns on warm, windy days, and for wind erosion where fields are bare.

Corn Belt and Ohio Valley

• Anticipate one broad precipitation event mid-period; otherwise, short dry spells favor field access, especially west. Cooler days after fronts slow soil evaporation but improve grain drying air.
• Potential for first/renewed snow cover in the north with the main system’s back side.

Delta and Southeast

• Intermittent shower lines with each front, quickly followed by dry, breezy air. Inland frost likely on the clearest, calmest nights; coastal citrus less impacted but still monitor low-lying cold pockets.
• Cool-season forage growth continues where moisture is adequate; disease pressure eases between rains.

Northeast

• Mixed precipitation event possible with the main system, then lake-effect snow in favored belts. Expect freeze–thaw cycles and localized icy conditions.
• Vineyards/orchards: Persistent leaf litter moisture can foster trunk disease; target pruning/sanitation during drier interludes.

Operational Planning Checklist (Next 7 Days)

• Frost/Freeze: Stage covers and irrigation for interior CA, AZ deserts, inland Southeast. Protect early citrus and tender vegetables in wind-sheltered lows.
• Wind: Secure row covers and greenhouse infrastructure ahead of frontal passages in the Plains and Midwest.
• Field Traffic: Use post-frontal, breezy periods for tillage and harvest; avoid compaction on saturated clays after any rain bands.
• Logistics: Plan Western mountain transits around snow windows; expect chain controls during and just after each wave.
• Grain Management: Leverage cool, dry air after fronts for natural-air drying; monitor condensation in bins with large diurnal swings.