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  <xs:element id="fcf_FinancingReceivablePurchasedWithoutCreditDeteriorationDiscountPremium" abstract="false" name="FinancingReceivablePurchasedWithoutCreditDeteriorationDiscountPremium" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_FinancingReceivablePurchasedWithoutCreditDeteriorationAmountAtPurchasePrice" abstract="false" name="FinancingReceivablePurchasedWithoutCreditDeteriorationAmountAtPurchasePrice" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFHLBStock" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFHLBStock" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedBankOwnedLifeInsurance" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedBankOwnedLifeInsurance" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherAssets" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDepositsContractualAmount" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDepositsContractualAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_CashPaidForInterestAndIncomeTaxesAbstract" abstract="true" name="CashPaidForInterestAndIncomeTaxesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="fcf_UnsettledBankOwnedLifeInsuranceProceeds" abstract="false" name="UnsettledBankOwnedLifeInsuranceProceeds" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_LoansTransferredtoOtherRealEstateOwnedandRepossessions" abstract="false" name="LoansTransferredtoOtherRealEstateOwnedandRepossessions" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_WeightedAverageNumberofSharesDeferredCompensationPlans" abstract="false" name="WeightedAverageNumberofSharesDeferredCompensationPlans" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="fcf_WeightedAverageNumberOfAdditionalSharesDeferredCompensationPlan" abstract="false" name="WeightedAverageNumberOfAdditionalSharesDeferredCompensationPlan" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="fcf_RestrictedStockUnitsMember" abstract="true" name="RestrictedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_CommercialLettersOfCreditMember" abstract="true" name="CommercialLettersOfCreditMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_NotionalAmountOfCommitmentsAndLettersOfCredit" abstract="false" name="NotionalAmountOfCommitmentsAndLettersOfCredit" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_NotionalAmountOfPerformanceStandbyLettersOfCredit" abstract="false" name="NotionalAmountOfPerformanceStandbyLettersOfCredit" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_NotionalAmountOfCommercialLettersOfCredit" abstract="false" name="NotionalAmountOfCommercialLettersOfCredit" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_NotionalAmountOfFinancialStandbyLettersOfCredit" abstract="false" name="NotionalAmountOfFinancialStandbyLettersOfCredit" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="fcf_USGovernmentAgencyDebtSecuritiesResidentialDomain" abstract="true" name="USGovernmentAgencyDebtSecuritiesResidentialDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_USGovernmentAgencyDebtSecuritiesCommercialMember" abstract="true" name="USGovernmentAgencyDebtSecuritiesCommercialMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_InvestmentSecuritiesLineItems" abstract="true" name="InvestmentSecuritiesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="fcf_SourceOfRealizedGainsLossesAxis" abstract="true" name="SourceOfRealizedGainsLossesAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fcf_SourceOfRealizedGainsLossesDomain" abstract="true" name="SourceOfRealizedGainsLossesDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_MaturitiesMember" abstract="true" name="MaturitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_GrossGains" abstract="false" name="GrossGains" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_GrossLosses" abstract="false" name="GrossLosses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_ScheduleOfUnrealizedLossesAndEstimatedFairValuesTable" abstract="true" name="ScheduleOfUnrealizedLossesAndEstimatedFairValuesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="fcf_USGovernmentAgenciesDebtSecuritiesCommercialMember" abstract="true" name="USGovernmentAgenciesDebtSecuritiesCommercialMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_CorporateSecuritiesMember" abstract="true" name="CorporateSecuritiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_ScheduleOfUnrealizedLossesAndEstimatedFairValuesLineItems" abstract="true" name="ScheduleOfUnrealizedLossesAndEstimatedFairValuesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="fcf_InvestmentSecuritiesContinuousUnrealizedLossPositionLessthanTwelveMonthsFairValue" abstract="false" name="InvestmentSecuritiesContinuousUnrealizedLossPositionLessthanTwelveMonthsFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_InvestmentSecuritiesContinuousUnrealizedLossPositionLessthan12MonthsAccumulatedLoss" abstract="false" name="InvestmentSecuritiesContinuousUnrealizedLossPositionLessthan12MonthsAccumulatedLoss" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_InvestmentSecuritiesContinuousUnrealizedLossPositionTwelveMonthsorLongerFairValue" abstract="false" name="InvestmentSecuritiesContinuousUnrealizedLossPositionTwelveMonthsorLongerFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_InvestmentSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAccumulatedLoss" abstract="false" name="InvestmentSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAccumulatedLoss" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_InvestmentSecuritiesContinuousUnrealizedLossPositionFairValueTotal" abstract="false" name="InvestmentSecuritiesContinuousUnrealizedLossPositionFairValueTotal" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_InvestmentSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss" abstract="false" name="InvestmentSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_AvailableForSaleSecuritiesSoldAxis" abstract="true" name="AvailableForSaleSecuritiesSoldAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fcf_AvailableForSaleSecuritiesSoldDomain" abstract="true" name="AvailableForSaleSecuritiesSoldDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_FCBPortfolioMember" abstract="true" name="FCBPortfolioMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_PercentOfUnrealizedLosses" abstract="false" name="PercentOfUnrealizedLosses" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fcf_InvestmentSecuritiesinUnrealizedLossPositionQualitativeDisclosureNumberofPositionsTotal" abstract="false" name="InvestmentSecuritiesinUnrealizedLossPositionQualitativeDisclosureNumberofPositionsTotal" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fcf_BookValueOfAvailableForSaleDebtSecuritiesSold" abstract="false" name="BookValueOfAvailableForSaleDebtSecuritiesSold" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_EquitySecuritiesFairValueGainLoss" abstract="false" name="EquitySecuritiesFairValueGainLoss" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_CommercialCreditCardsMember" abstract="true" name="CommercialCreditCardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_ConsumerCreditCardsMember" abstract="true" name="ConsumerCreditCardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_EquipmentFinanceMember" abstract="true" name="EquipmentFinanceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_DefaultStatusOfModificationsAfterNumberOfDaysPastDue" abstract="false" name="DefaultStatusOfModificationsAfterNumberOfDaysPastDue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fcf_TermLoanReceivableOriginatedInCurrentYearMember" abstract="true" name="TermLoanReceivableOriginatedInCurrentYearMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_TermLoanReceivableOriginatedInOneYearPriorMember" abstract="true" name="TermLoanReceivableOriginatedInOneYearPriorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_TermLoanReceivableOriginatedTwoYearsPriorMember" abstract="true" name="TermLoanReceivableOriginatedTwoYearsPriorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_TermLoanReceivableOriginatedThreeYearsPriorMember" abstract="true" name="TermLoanReceivableOriginatedThreeYearsPriorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_TermLoanReceivableOriginatedFourYearsPriorMember" abstract="true" name="TermLoanReceivableOriginatedFourYearsPriorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_TermLoanReceivableOriginatedFiveOrMoreYearsPriorMember" abstract="true" name="TermLoanReceivableOriginatedFiveOrMoreYearsPriorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_RevolvingLoansReceivableMember" abstract="true" name="RevolvingLoansReceivableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_NonAccrualLoansMember" abstract="true" name="NonAccrualLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_WithNoRelatedAllowanceMember" abstract="true" name="WithNoRelatedAllowanceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_WithARelatedAllowanceMember" abstract="true" name="WithARelatedAllowanceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_FinancingReceivableNonaccrualUnpaidPrincipalBalance" abstract="false" name="FinancingReceivableNonaccrualUnpaidPrincipalBalance" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_FinancingReceivableNonaccrualRelatedAllowance" abstract="false" name="FinancingReceivableNonaccrualRelatedAllowance" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_NonperformingFinancingReceivableWithARelatedAllowanceAverageRecordedInvestment" abstract="false" name="NonperformingFinancingReceivableWithARelatedAllowanceAverageRecordedInvestment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_NonperformingFinancingReceivableAverageRecordedInvestment" abstract="false" name="NonperformingFinancingReceivableAverageRecordedInvestment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_NonperformingFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment" abstract="false" name="NonperformingFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_NonperformingFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod" abstract="false" name="NonperformingFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_NonperformingFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod" abstract="false" name="NonperformingFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_NonperformingFinancingReceivableInterestIncomeCashBasisMethod" abstract="false" name="NonperformingFinancingReceivableInterestIncomeCashBasisMethod" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_ExtendedMaturityAndPaymentDeferralMember" abstract="true" name="ExtendedMaturityAndPaymentDeferralMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_ContractualInterestRateReductionAndPaymentDeferralMember" abstract="true" name="ContractualInterestRateReductionAndPaymentDeferralMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_ContractualInterestRateReductionTermExtensionAndPaymentDeferralMember" abstract="true" name="ContractualInterestRateReductionTermExtensionAndPaymentDeferralMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_FinancingReceivableModifiedPaymentDeferral" abstract="false" name="FinancingReceivableModifiedPaymentDeferral" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:weightItemType"/>
  <xs:element id="fcf_FinancingReceivableModifiedInPeriodAgingAmount" abstract="false" name="FinancingReceivableModifiedInPeriodAgingAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_NonaccrualCommercialLoansAxis" abstract="true" name="NonaccrualCommercialLoansAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fcf_NonaccrualCommercialLoansDomain" abstract="true" name="NonaccrualCommercialLoansDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_NonaccrualCommercialLoansMember" abstract="true" name="NonaccrualCommercialLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_ChargeoffsAxis" abstract="true" name="ChargeoffsAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fcf_ChargeoffsDomain" abstract="true" name="ChargeoffsDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="fcf_NonperformingLoansDomain" abstract="true" name="NonperformingLoansDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_NonaccrualLoansPaidOffAxis" abstract="true" name="NonaccrualLoansPaidOffAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fcf_NonaccrualLoansPaidOffDomain" abstract="true" name="NonaccrualLoansPaidOffDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_IncreasesDecreasesinTroubledDebtRestructuringsAxis" abstract="true" name="IncreasesDecreasesinTroubledDebtRestructuringsAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fcf_IncreasesDecreasesinTroubledDebtRestructuringsDomain" abstract="true" name="IncreasesDecreasesinTroubledDebtRestructuringsDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_PartofLoanRelationshipAxis" abstract="true" name="PartofLoanRelationshipAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fcf_PartofLoanRelationshipDomain" abstract="true" name="PartofLoanRelationshipDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="fcf_IncreasesinNonperformingLoansDomain" abstract="true" name="IncreasesinNonperformingLoansDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_LoanToDifferentProjectAxis" abstract="true" name="LoanToDifferentProjectAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fcf_LoanToDifferentProjectDomain" abstract="true" name="LoanToDifferentProjectDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_NetDeferredFeesMember" abstract="true" name="NetDeferredFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_UnearnedPremiumsAndDiscountsMember" abstract="true" name="UnearnedPremiumsAndDiscountsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_SmallBusinessAdministrationGuaranteeMember" abstract="true" name="SmallBusinessAdministrationGuaranteeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_NonAccrualStatusOfLoansAfterNumberOfDaysPastDue" abstract="false" name="NonAccrualStatusOfLoansAfterNumberOfDaysPastDue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fcf_UnfundedCommitmentsRelatedToNonperformingLoans" abstract="false" name="UnfundedCommitmentsRelatedToNonperformingLoans" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_OffBalanceSheetReserveToNonperformingLoans" abstract="false" name="OffBalanceSheetReserveToNonperformingLoans" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_ForecastedValueNationalUnemploymentPercent" abstract="false" name="ForecastedValueNationalUnemploymentPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fcf_UnearnedDeferredFeesCostsOnLoans" abstract="false" name="UnearnedDeferredFeesCostsOnLoans" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_FinancingReceivableModifiedSubsequentDefaultNumberOfContracts" abstract="false" name="FinancingReceivableModifiedSubsequentDefaultNumberOfContracts" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fcf_ImpairedLoansFairValue" abstract="false" name="ImpairedLoansFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fcf_OtherRealEstateOwnedAssetsFairValue" abstract="false" name="OtherRealEstateOwnedAssetsFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="fcf_FairValueMeasurementOfAssetsOnNonrecurringBasisNetLossesOnLoansHeldForSale" abstract="false" name="FairValueMeasurementOfAssetsOnNonrecurringBasisNetLossesOnLoansHeldForSale" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="fcf_InterestRateMacroSwapMember" abstract="true" name="InterestRateMacroSwapMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="fcf_RiskParticipationAgreementsDomain" abstract="true" name="RiskParticipationAgreementsDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_RiskParticipationAgreementsPurchasedDomain" abstract="true" name="RiskParticipationAgreementsPurchasedDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_RiskParticipationAgreementsSoldDomain" abstract="true" name="RiskParticipationAgreementsSoldDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fcf_MaturityDateAxis" abstract="true" name="MaturityDateAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fcf_MaturityDateDomain" abstract="true" name="MaturityDateDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="fcf_DerivativeInstrumentsDesignatedAsHedgingInstrumentsInterestExpense" abstract="false" name="DerivativeInstrumentsDesignatedAsHedgingInstrumentsInterestExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="fcf_DerivativeInstrumentsDesignatedAsHedgingInstrumentsInterestIncome" abstract="false" name="DerivativeInstrumentsDesignatedAsHedgingInstrumentsInterestIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="fcf_FirstCommonwealthFinancialCorporationMember" abstract="true" name="FirstCommonwealthFinancialCorporationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="fcf_InScopeofTopic606Member" abstract="true" name="InScopeofTopic606Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="fcf_AdditionalInformationAbstract" abstract="true" name="AdditionalInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
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  <xs:element id="fcf_AdjustmentsAndReconcilingItemsSegmentNetIncome" abstract="false" name="AdjustmentsAndReconcilingItemsSegmentNetIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
