Federal Contract Weather Delays
Federal weather claims are less about persuasion than private ones and more about arithmetic — because the government usually tells you up front how much bad weather it expects. The trap is not the standard. It is the ten-day clock.
Find your clause first
Two FAR clauses carry weather, and which one governs depends on your contract type, not your scope of work:
| Clause | Applies to | Remedy |
|---|---|---|
| FAR 52.249-10 — Default (Fixed-Price Construction) | Fixed-price construction | Time extension |
| FAR 52.249-14 — Excusable Delays | Cost-reimbursement, time-and-materials, labor-hour | Time extension |
Both list the same causes beyond the contractor's control and without its fault or negligence — acts of God, acts of the Government, fires, floods, epidemics, quarantine restrictions, strikes, freight embargoes, and unusually severe weather. Neither defines the phrase. For what it means in the abstract, see unusually severe weather: what actually counts.
The 10-day clock
FAR 52.249-10 requires written notice to the Contracting Officer within 10 days from the beginning of the delay — not from when you finished quantifying it, and not from when the month ended. The CO may extend that period, but only if you ask before it runs.
Ten days is aggressive by design, and it catches subs who are used to A201's twenty-one. Worse, it starts at the beginning of the delay, which on a rain event is the first unworkable day — often days before anyone on site has decided this is going to be a claim at all.
The practical answer is to lower the threshold for sending notice. A short letter identifying the event, the dates and the affected activities preserves the claim. The analysis can follow.
The part that makes federal claims different
Most federal construction contracts do not leave "unusual" to argument. They include a Time Extensions for Unusually Severe Weather clause with a table of anticipated adverse weather delay work days for each calendar month — typically built from NOAA records for the project location and stated as workdays on a five-day week.
Where that table exists, the entitlement calculation is mechanical:
Time extension = actual adverse weather delay work days − anticipated days for that month
That is a genuinely better deal than the private-sector standard, and most subs underuse it. You are not arguing about whether the weather was unusual; the government already conceded a number. You are proving you exceeded it. Three consequences worth internalising:
- A month can be claimable without being remarkable. If the table anticipates 4 days in October and you lost 7, you have a 3-day extension — no dramatic storm required.
- The historical baseline argument is over. Do not build an exhibit proving the month was worse than the 10-year norm when the contract already fixed the number. Use theirs.
- Unused anticipated days do not bank. The comparison is month by month. A dry September does not create credit against a wet October.
What counts as an "adverse weather delay work day"
This is where federal claims are actually won and lost, because the contract usually defines it — and the definition is stricter than "it rained."
Typical contract language requires that the day be a scheduled workday, that adverse weather prevent work for a defined portion of the day (often 50% or more of the shift), and that the affected work be on the critical path of the accepted schedule. Some agencies specify a precipitation threshold; the USACE/NAVFAC Unified Facilities Guide Specifications for network analysis schedules carry adverse-weather lost-work-day provisions that tie the count directly into the schedule updates rather than a separate log.
Read your definition before you count anything. If the contract says a weather day requires four hours lost on critical work, counting calendar days with measurable rain will overstate your claim — and an overstated claim invites scrutiny of the days that were legitimate.
Drying days are claimable, and usually uncounted
Nothing in this language limits the impact to precipitation falling. If saturated subgrade made the site untrafficable two days after the storm, those are adverse weather delay work days on the same terms as the storm itself — provided you can show the ground condition rather than assert it. On earthwork-heavy federal jobs the drying tail is frequently larger than the rain event that caused it; see jobsite soil drying time by soil type.
Time, not money
Both clauses provide an extension of the contract time and nothing else. Unusually severe weather is the textbook excusable but non-compensable delay: it defeats a default termination and stops liquidated damages from accruing, but idle crew, extended field office and equipment standby stay on your side of the ledger.
The exception worth watching for is concurrency with a government-caused delay. If a differing site condition or a late government response overlaps the weather period, the compensability analysis changes and it is worth a claims consultant's time.
Checklist
- Identify whether 52.249-10 or 52.249-14 is in your contract.
- Find the anticipated adverse weather table, if there is one. That is your baseline.
- Find the contract's definition of an adverse weather delay work day, including any hours or precipitation threshold.
- Send written notice to the CO inside 10 days of the delay beginning — thin and timely.
- Track weather days in the schedule updates, not only in the daily log, and show the critical-path impact.
- Count the drying tail, with soil evidence.
Build the record before you need it
Ilystics pulls a 10-year NOAA baseline and USDA soil drying analysis for your exact jobsite — useful both for sanity-checking an anticipated-days table at bid time and for documenting actual lost days during the job. Free, no account.
Generate a Free ExhibitAlready in a dispute? Request a $249 Claim Report for the actual-vs-baseline analysis.
Ilystics provides weather and soil analysis, not legal advice. References are to FAR 52.249-10 and 52.249-14 and to common federal construction contract provisions, and are provided for general orientation only. Clause content, anticipated-weather tables and the definition of an adverse weather delay work day vary by agency, solicitation and contract version — your contract controls. Federal claims are governed by the Contract Disputes Act and agency procedures; consult your attorney or claims consultant on entitlement and on preserving your rights.